cve-2026-23111
HIGH CVSS 7.8 nvd
Description
In the Linux kernel, the following vulnerability has been resolved: netfilter: nf_tables: fix inverted genmask check in nft_map_catchall_activate() nft_map_catchall_activate() has an inverted element activity check compared to its non-catchall counterpart nft_mapelem_activate() and compared to what is logically required. nft_map_catchall_activate() is called from the abort path to re-activate catchall map elements that were deactivated during a failed transaction. It should skip elements that are already active (they don't need re-activation) and process elements that are inactive (they need to be restored). Instead, the current code does the opposite: it skips inactive elements and processes active ones. Compare the non-catchall activate callback, which is correct: nft_mapelem_activate(): if (nft_set_elem_active(ext, iter->genmask)) return 0; /* skip active, process inactive */ With the buggy catchall version: nft_map_catchall_activate(): if (!nft_set_elem_active(ext, genmask)) continue; /* skip inactive, process active */ The consequence is that when a DELSET operation is aborted, nft_setelem_data_activate() is never called for the catchall element. For NFT_GOTO verdict elements, this means nft_data_hold() is never called to restore the chain->use reference count. Each abort cycle permanently decrements chain->use. Once chain->use reaches zero, DELCHAIN succeeds and frees the chain while catchall verdict elements still reference it, resulting in a use-after-free. This is exploitable for local privilege escalation from an unprivileged user via user namespaces + nftables on distributions that enable CONFIG_USER_NS and CONFIG_NF_TABLES. Fix by removing the negation so the check matches nft_mapelem_activate(): skip active elements, process inactive ones.
Timeline
- Published
- 2026-02-13
- Last Modified
- 2026-09-03
CVSS Details
- Attack Vector
- LOCAL
- Attack Complexity
- LOW
- Privileges Required
- LOW
Affected Products
- linux linux_kernel
CVSS metrics
| Version | Base | Severity | Vector | Exploitability | Impact | Source |
|---|---|---|---|---|---|---|
| 3.1 | 7.8 | HIGH | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H |
1.8 | 5.9 | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 |
| 3.1 | 7.8 | HIGH | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H |
1.8 | 5.9 | nvd@nist.gov |
| 3.1 | 7.8 | HIGH | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H |
1.8 | 5.9 | 0b0ca135-0b70-47e7-9f44-1890c2a1c46c |
CPE configurations
OR
| CPE | Version range | Vulnerable |
|---|---|---|
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* |
>= 4.19.316, < 4.20 | yes |
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* |
>= 5.4.262, < 5.5 | yes |
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* |
>= 5.10.188, < 5.11 | yes |
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* |
>= 5.15.121, < 5.15.200 | yes |
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* |
>= 6.1.36, < 6.1.163 | yes |
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* |
>= 6.3.10, < 6.4 | yes |
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* |
>= 6.4.1, < 6.6.124 | yes |
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* |
>= 6.7, < 6.12.70 | yes |
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* |
>= 6.13, < 6.18.10 | yes |
cpe:2.3:o:linux:linux_kernel:6.4:-:*:*:*:*:*:* |
— | yes |
cpe:2.3:o:linux:linux_kernel:6.19:rc1:*:*:*:*:*:* |
— | yes |
cpe:2.3:o:linux:linux_kernel:6.19:rc2:*:*:*:*:*:* |
— | yes |
cpe:2.3:o:linux:linux_kernel:6.19:rc3:*:*:*:*:*:* |
— | yes |
cpe:2.3:o:linux:linux_kernel:6.19:rc4:*:*:*:*:*:* |
— | yes |
cpe:2.3:o:linux:linux_kernel:6.19:rc5:*:*:*:*:*:* |
— | yes |
cpe:2.3:o:linux:linux_kernel:6.19:rc6:*:*:*:*:*:* |
— | yes |
cpe:2.3:o:linux:linux_kernel:6.19:rc7:*:*:*:*:*:* |
— | yes |
cpe:2.3:o:linux:linux_kernel:6.19:rc8:*:*:*:*:*:* |
— | yes |
NVD metadata
- NVD status
- Modified
- Source identifier
416baaa9-dc9f-4396-8d5f-8c081fb06d67
References
- https://git.kernel.org/stable/c/1444ff890b4653add12f734ffeffc173d42862dd Patch
- https://git.kernel.org/stable/c/42c574c1504aa089a0a142e4c13859327570473d Patch
- https://git.kernel.org/stable/c/8b68a45f9722f2babe9e7bad00aa74638addf081 Patch
- https://git.kernel.org/stable/c/8c760ba4e36c750379d13569f23f5a6e185333f5 Patch
- https://git.kernel.org/stable/c/b9b6573421de51829f7ec1cce76d85f5f6fbbd7f Patch
- https://git.kernel.org/stable/c/f41c5d151078c5348271ffaf8e7410d96f2d82f8 Patch
- https://access.redhat.com/errata/RHSA-2026:10108
- https://access.redhat.com/errata/RHSA-2026:10996
- https://access.redhat.com/errata/RHSA-2026:18134
- https://access.redhat.com/errata/RHSA-2026:62639
- https://access.redhat.com/errata/RHSA-2026:62641
- https://access.redhat.com/errata/RHSA-2026:6570
- https://access.redhat.com/errata/RHSA-2026:9112
- https://access.redhat.com/security/cve/CVE-2026-23111
- https://blog.exodusintel.com/2026/06/08/off-by-exploiting-a-use-after-free-in-the-linux-kernel/
- https://bugzilla.redhat.com/show_bug.cgi?id=2439687
- https://cert-portal.siemens.com/productcert/html/ssa-019113.html
- https://cert-portal.siemens.com/productcert/html/ssa-082556.html
- https://cert-portal.siemens.com/productcert/html/ssa-253495.html
- https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-23111.json
Linked Vulnerabilities
{
"cvss": 7.8,
"datePublished": "2026-02-13T14:16:10.283",
"dateUpdated": "2026-09-03T13:04:45.447",
"description": "In the Linux kernel, the following vulnerability has been resolved:\n\nnetfilter: nf_tables: fix inverted genmask check in nft_map_catchall_activate()\n\nnft_map_catchall_activate() has an inverted element activity check\ncompared to its non-catchall counterpart nft_mapelem_activate() and\ncompared to what is logically required.\n\nnft_map_catchall_activate() is called from the abort path to re-activate\ncatchall map elements that were deactivated during a failed transaction.\nIt should skip elements that are already active (they don't need\nre-activation) and process elements that are inactive (they need to be\nrestored). Instead, the current code does the opposite: it skips inactive\nelements and processes active ones.\n\nCompare the non-catchall activate callback, which is correct:\n\n nft_mapelem_activate():\n if (nft_set_elem_active(ext, iter->genmask))\n return 0; /* skip active, process inactive */\n\nWith the buggy catchall version:\n\n nft_map_catchall_activate():\n if (!nft_set_elem_active(ext, genmask))\n continue; /* skip inactive, process active */\n\nThe consequence is that when a DELSET operation is aborted,\nnft_setelem_data_activate() is never called for the catchall element.\nFor NFT_GOTO verdict elements, this means nft_data_hold() is never\ncalled to restore the chain->use reference count. Each abort cycle\npermanently decrements chain->use. Once chain->use reaches zero,\nDELCHAIN succeeds and frees the chain while catchall verdict elements\nstill reference it, resulting in a use-after-free.\n\nThis is exploitable for local privilege escalation from an unprivileged\nuser via user namespaces + nftables on distributions that enable\nCONFIG_USER_NS and CONFIG_NF_TABLES.\n\nFix by removing the negation so the check matches nft_mapelem_activate():\nskip active elements, process inactive ones.",
"id": "CVE-2026-23111",
"raw": {
"affected": [
{
"affectedData": [
{
"defaultStatus": "unaffected",
"product": "Linux",
"programFiles": [
"net/netfilter/nf_tables_api.c"
],
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"versions": [
{
"lessThan": "8c760ba4e36c750379d13569f23f5a6e185333f5",
"status": "affected",
"version": "25aa2ad37c2162be1c0bc4fe6397f7e4c13f00f8",
"versionType": "git"
},
{
"lessThan": "b9b6573421de51829f7ec1cce76d85f5f6fbbd7f",
"status": "affected",
"version": "d60be2da67d172aecf866302c91ea11533eca4d9",
"versionType": "git"
},
{
"lessThan": "42c574c1504aa089a0a142e4c13859327570473d",
"status": "affected",
"version": "628bd3e49cba1c066228e23d71a852c23e26da73",
"versionType": "git"
},
{
"lessThan": "1444ff890b4653add12f734ffeffc173d42862dd",
"status": "affected",
"version": "628bd3e49cba1c066228e23d71a852c23e26da73",
"versionType": "git"
},
{
"lessThan": "8b68a45f9722f2babe9e7bad00aa74638addf081",
"status": "affected",
"version": "628bd3e49cba1c066228e23d71a852c23e26da73",
"versionType": "git"
},
{
"lessThan": "f41c5d151078c5348271ffaf8e7410d96f2d82f8",
"status": "affected",
"version": "628bd3e49cba1c066228e23d71a852c23e26da73",
"versionType": "git"
},
{
"status": "affected",
"version": "bc9f791d2593f17e39f87c6e2b3a36549a3705b1",
"versionType": "git"
},
{
"status": "affected",
"version": "3c7ec098e3b588434a8b07ea9b5b36f04cef1f50",
"versionType": "git"
},
{
"status": "affected",
"version": "a136b7942ad2a50de708f76ea299ccb45ac7a7f9",
"versionType": "git"
},
{
"status": "affected",
"version": "dc7cdf8cbcbf8b13de1df93f356ec04cdeef5c41",
"versionType": "git"
},
{
"lessThan": "5.15.200",
"status": "affected",
"version": "5.15.121",
"versionType": "semver"
},
{
"lessThan": "6.1.163",
"status": "affected",
"version": "6.1.36",
"versionType": "semver"
},
{
"lessThan": "4.20",
"status": "affected",
"version": "4.19.316",
"versionType": "semver"
},
{
"lessThan": "5.5",
"status": "affected",
"version": "5.4.262",
"versionType": "semver"
},
{
"lessThan": "5.11",
"status": "affected",
"version": "5.10.188",
"versionType": "semver"
},
{
"lessThan": "6.4",
"status": "affected",
"version": "6.3.10",
"versionType": "semver"
}
]
},
{
"defaultStatus": "affected",
"product": "Linux",
"programFiles": [
"net/netfilter/nf_tables_api.c"
],
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"versions": [
{
"status": "affected",
"version": "6.4"
},
{
"lessThan": "6.4",
"status": "unaffected",
"version": "0",
"versionType": "semver"
},
{
"lessThanOrEqual": "5.15.*",
"status": "unaffected",
"version": "5.15.200",
"versionType": "semver"
},
{
"lessThanOrEqual": "6.1.*",
"status": "unaffected",
"version": "6.1.163",
"versionType": "semver"
},
{
"lessThanOrEqual": "6.6.*",
"status": "unaffected",
"version": "6.6.124",
"versionType": "semver"
},
{
"lessThanOrEqual": "6.12.*",
"status": "unaffected",
"version": "6.12.70",
"versionType": "semver"
},
{
"lessThanOrEqual": "6.18.*",
"status": "unaffected",
"version": "6.18.10",
"versionType": "semver"
},
{
"lessThanOrEqual": "*",
"status": "unaffected",
"version": "6.19",
"versionType": "original_commit_for_fix"
}
]
}
],
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"affectedData": [
{
"collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
"cpes": [
"cpe:/o:redhat:enterprise_linux:10.2"
],
"defaultStatus": "affected",
"packageName": "kernel",
"product": "Red Hat Enterprise Linux 10",
"vendor": "Red Hat",
"versions": [
{
"lessThan": "*",
"status": "unaffected",
"version": "0:6.12.0-211.7.1.el10_2",
"versionType": "rpm"
}
]
},
{
"collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
"cpes": [
"cpe:/o:redhat:enterprise_linux_eus:10.0"
],
"defaultStatus": "affected",
"packageName": "kernel",
"product": "Red Hat Enterprise Linux 10.0 Extended Update Support",
"vendor": "Red Hat",
"versions": [
{
"lessThan": "*",
"status": "unaffected",
"version": "0:6.12.0-55.70.1.el10_0",
"versionType": "rpm"
}
]
},
{
"collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
"cpes": [
"cpe:/a:redhat:enterprise_linux:9",
"cpe:/o:redhat:enterprise_linux:9"
],
"defaultStatus": "affected",
"packageName": "kernel",
"product": "Red Hat Enterprise Linux 9",
"vendor": "Red Hat",
"versions": [
{
"lessThan": "*",
"status": "unaffected",
"version": "0:5.14.0-611.47.1.el9_7",
"versionType": "rpm"
}
]
},
{
"collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
"cpes": [
"cpe:/a:redhat:rhel_eus:9.4"
],
"defaultStatus": "affected",
"packageName": "kernel",
"product": "Red Hat Enterprise Linux 9.4 Extended Update Support",
"vendor": "Red Hat",
"versions": [
{
"lessThan": "*",
"status": "unaffected",
"version": "0:5.14.0-427.121.1.el9_4",
"versionType": "rpm"
}
]
},
{
"collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
"cpes": [
"cpe:/a:redhat:rhel_eus:9.6"
],
"defaultStatus": "affected",
"packageName": "kernel",
"product": "Red Hat Enterprise Linux 9.6 Extended Update Support",
"vendor": "Red Hat",
"versions": [
{
"lessThan": "*",
"status": "unaffected",
"version": "0:5.14.0-570.108.1.el9_6",
"versionType": "rpm"
}
]
},
{
"collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
"cpes": [
"cpe:/o:redhat:enterprise_linux:6"
],
"defaultStatus": "unaffected",
"packageName": "kernel",
"product": "Red Hat Enterprise Linux 6",
"vendor": "Red Hat"
},
{
"collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
"cpes": [
"cpe:/o:redhat:enterprise_linux:7"
],
"defaultStatus": "unaffected",
"packageName": "kernel",
"product": "Red Hat Enterprise Linux 7",
"vendor": "Red Hat"
},
{
"collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
"cpes": [
"cpe:/o:redhat:enterprise_linux:7"
],
"defaultStatus": "unaffected",
"packageName": "kernel-rt",
"product": "Red Hat Enterprise Linux 7",
"vendor": "Red Hat"
},
{
"collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
"cpes": [
"cpe:/o:redhat:enterprise_linux:8"
],
"defaultStatus": "unaffected",
"packageName": "kernel",
"product": "Red Hat Enterprise Linux 8",
"vendor": "Red Hat"
},
{
"collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
"cpes": [
"cpe:/o:redhat:enterprise_linux:8"
],
"defaultStatus": "unaffected",
"packageName": "kernel-rt",
"product": "Red Hat Enterprise Linux 8",
"vendor": "Red Hat"
},
{
"collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
"cpes": [
"cpe:/o:redhat:enterprise_linux:9"
],
"defaultStatus": "affected",
"packageName": "kernel-rt",
"product": "Red Hat Enterprise Linux 9",
"vendor": "Red Hat"
}
],
"source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c"
},
{
"affectedData": [
{
"defaultStatus": "unknown",
"product": "RUGGEDCOM RST2428P",
"vendor": "Siemens",
"versions": [
{
"lessThan": "V4.0",
"status": "affected",
"version": "0",
"versionType": "custom"
}
]
},
{
"defaultStatus": "unknown",
"product": "SIMATIC S7-1500 CPU 1518-4 PN/DP MFP",
"vendor": "Siemens",
"versions": [
{
"lessThan": "*",
"status": "affected",
"version": "V3.1.6",
"versionType": "custom"
}
]
},
{
"defaultStatus": "unknown",
"product": "SIMATIC S7-1500 CPU 1518-4 PN/DP MFP",
"vendor": "Siemens",
"versions": [
{
"lessThan": "*",
"status": "affected",
"version": "V3.1.5",
"versionType": "custom"
}
]
},
{
"defaultStatus": "unknown",
"product": "SIMATIC S7-1500 CPU 1518-4 PN/DP MFP",
"vendor": "Siemens",
"versions": [
{
"lessThan": "*",
"status": "affected",
"version": "V3.1.6",
"versionType": "custom"
}
]
},
{
"defaultStatus": "unknown",
"product": "SIMATIC S7-1500 CPU 1518-4 PN/DP MFP",
"vendor": "Siemens",
"versions": [
{
"lessThan": "*",
"status": "affected",
"version": "V3.1.5",
"versionType": "custom"
}
]
},
{
"defaultStatus": "unknown",
"product": "SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP",
"vendor": "Siemens",
"versions": [
{
"lessThan": "*",
"status": "affected",
"version": "V3.1.6",
"versionType": "custom"
}
]
},
{
"defaultStatus": "unknown",
"product": "SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP",
"vendor": "Siemens",
"versions": [
{
"lessThan": "*",
"status": "affected",
"version": "V3.1.5",
"versionType": "custom"
}
]
},
{
"defaultStatus": "unknown",
"product": "SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP",
"vendor": "Siemens",
"versions": [
{
"lessThan": "*",
"status": "affected",
"version": "V3.1.6",
"versionType": "custom"
}
]
},
{
"defaultStatus": "unknown",
"product": "SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP",
"vendor": "Siemens",
"versions": [
{
"lessThan": "*",
"status": "affected",
"version": "V3.1.5",
"versionType": "custom"
}
]
},
{
"defaultStatus": "unknown",
"product": "SIPLUS S7-1500 CPU 1518-4 PN/DP MFP",
"vendor": "Siemens",
"versions": [
{
"lessThan": "*",
"status": "affected",
"version": "V3.1.6",
"versionType": "custom"
}
]
},
{
"defaultStatus": "unknown",
"product": "SIPLUS S7-1500 CPU 1518-4 PN/DP MFP",
"vendor": "Siemens",
"versions": [
{
"lessThan": "*",
"status": "affected",
"version": "V3.1.5",
"versionType": "custom"
}
]
}
],
"source": "0b142b55-0307-4c5a-b3c9-f314f3fb7c5e"
}
],
"configurations": [
{
"nodes": [
{
"cpeMatch": [
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"matchCriteriaId": "76EC9BF9-9775-4D90-B594-4C2AB71E1F86",
"versionEndExcluding": "4.20",
"versionStartIncluding": "4.19.316",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"matchCriteriaId": "5CE7F771-8144-4AEC-B6E3-5F4830BD8EB7",
"versionEndExcluding": "5.5",
"versionStartIncluding": "5.4.262",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"matchCriteriaId": "6D42E8C7-CD33-432A-AC09-DC524C88ECE4",
"versionEndExcluding": "5.11",
"versionStartIncluding": "5.10.188",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"matchCriteriaId": "2EA37A2D-57E0-4A43-A252-503102E540FF",
"versionEndExcluding": "5.15.200",
"versionStartIncluding": "5.15.121",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"matchCriteriaId": "1D546C31-A384-495B-8C0A-A791FD646888",
"versionEndExcluding": "6.1.163",
"versionStartIncluding": "6.1.36",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"matchCriteriaId": "3E002324-2B5E-4373-A29E-1D5D0FC97F6F",
"versionEndExcluding": "6.4",
"versionStartIncluding": "6.3.10",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"matchCriteriaId": "08EA1902-1FF1-4739-8B3E-5340B3E41010",
"versionEndExcluding": "6.6.124",
"versionStartIncluding": "6.4.1",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"matchCriteriaId": "F3791390-0628-4808-99EF-1ED8ABF60933",
"versionEndExcluding": "6.12.70",
"versionStartIncluding": "6.7",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"matchCriteriaId": "7156C23F-009E-4D05-838C-A2DA417B5B8D",
"versionEndExcluding": "6.18.10",
"versionStartIncluding": "6.13",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:6.4:-:*:*:*:*:*:*",
"matchCriteriaId": "DE0B0BF6-0EEF-4FAD-927D-7A0DD77BEE75",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:6.19:rc1:*:*:*:*:*:*",
"matchCriteriaId": "17B67AA7-40D6-4AFA-8459-F200F3D7CFD1",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:6.19:rc2:*:*:*:*:*:*",
"matchCriteriaId": "C47E4CC9-C826-4FA9-B014-7FE3D9B318B2",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:6.19:rc3:*:*:*:*:*:*",
"matchCriteriaId": "F71D92C0-C023-48BD-B3B6-70B638EEE298",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:6.19:rc4:*:*:*:*:*:*",
"matchCriteriaId": "13580667-0A98-40CC-B29F-D12790B91BDB",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:6.19:rc5:*:*:*:*:*:*",
"matchCriteriaId": "CAD1FED7-CF48-47BF-AC7D-7B6FA3C065FC",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:6.19:rc6:*:*:*:*:*:*",
"matchCriteriaId": "3EF854A1-ABB1-4E93-BE9A-44569EC76C0D",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:6.19:rc7:*:*:*:*:*:*",
"matchCriteriaId": "F5DC0CA6-F0AF-4DDF-A882-3DADB9A886A7",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:6.19:rc8:*:*:*:*:*:*",
"matchCriteriaId": "EB5B7DFC-C36B-45D8-922C-877569FDDF43",
"vulnerable": true
}
],
"negate": false,
"operator": "OR"
}
]
}
],
"cveTags": [],
"descriptions": [
{
"lang": "en",
"value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnetfilter: nf_tables: fix inverted genmask check in nft_map_catchall_activate()\n\nnft_map_catchall_activate() has an inverted element activity check\ncompared to its non-catchall counterpart nft_mapelem_activate() and\ncompared to what is logically required.\n\nnft_map_catchall_activate() is called from the abort path to re-activate\ncatchall map elements that were deactivated during a failed transaction.\nIt should skip elements that are already active (they don't need\nre-activation) and process elements that are inactive (they need to be\nrestored). Instead, the current code does the opposite: it skips inactive\nelements and processes active ones.\n\nCompare the non-catchall activate callback, which is correct:\n\n nft_mapelem_activate():\n if (nft_set_elem_active(ext, iter->genmask))\n return 0; /* skip active, process inactive */\n\nWith the buggy catchall version:\n\n nft_map_catchall_activate():\n if (!nft_set_elem_active(ext, genmask))\n continue; /* skip inactive, process active */\n\nThe consequence is that when a DELSET operation is aborted,\nnft_setelem_data_activate() is never called for the catchall element.\nFor NFT_GOTO verdict elements, this means nft_data_hold() is never\ncalled to restore the chain->use reference count. Each abort cycle\npermanently decrements chain->use. Once chain->use reaches zero,\nDELCHAIN succeeds and frees the chain while catchall verdict elements\nstill reference it, resulting in a use-after-free.\n\nThis is exploitable for local privilege escalation from an unprivileged\nuser via user namespaces + nftables on distributions that enable\nCONFIG_USER_NS and CONFIG_NF_TABLES.\n\nFix by removing the negation so the check matches nft_mapelem_activate():\nskip active elements, process inactive ones."
},
{
"lang": "es",
"value": "En el kernel de Linux, la siguiente vulnerabilidad ha sido resuelta:\n\nnetfilter: nf_tables: corrección de la comprobación genmask invertida en nft_map_catchall_activate()\n\nnft_map_catchall_activate() tiene una comprobación de actividad de elemento invertida en comparación con su contraparte no-catchall nft_mapelem_activate() y en comparación con lo que se requiere lógicamente.\n\nnft_map_catchall_activate() es llamada desde la ruta de aborto para reactivar elementos de mapa catchall que fueron desactivados durante una transacción fallida. Debería omitir los elementos que ya están activos (no necesitan reactivación) y procesar los elementos que están inactivos (necesitan ser restaurados). En cambio, el código actual hace lo contrario: omite los elementos inactivos y procesa los activos.\n\nCompare la devolución de llamada de activación no-catchall, que es correcta:\n\n nft_mapelem_activate():\n if (nft_set_elem_active(ext, iter->genmask))\n return 0; /* omitir activos, procesar inactivos */\n\nCon la versión catchall con errores:\n\n nft_map_catchall_activate():\n if (!nft_set_elem_active(ext, genmask))\n continue; /* omitir inactivos, procesar activos */\n\nLa consecuencia es que cuando una operación DELSET es abortada, nft_setelem_data_activate() nunca es llamada para el elemento catchall. Para los elementos de veredicto NFT_GOTO, esto significa que nft_data_hold() nunca es llamada para restaurar el contador de referencias chain->use. Cada ciclo de aborto decrementa permanentemente chain->use. Una vez que chain->use llega a cero, DELCHAIN tiene éxito y libera la cadena mientras que los elementos de veredicto catchall aún la referencian, resultando en un uso después de liberación.\n\nEsto es explotable para escalada de privilegios local desde un usuario sin privilegios a través de espacios de nombres de usuario + nftables en distribuciones que habilitan CONFIG_USER_NS y CONFIG_NF_TABLES.\n\nCorrección eliminando la negación para que la comprobación coincida con nft_mapelem_activate(): omitir elementos activos, procesar inactivos."
}
],
"id": "CVE-2026-23111",
"lastModified": "2026-09-03T13:04:45.447",
"metrics": {
"cvssMetricV31": [
{
"cvssData": {
"attackComplexity": "LOW",
"attackVector": "LOCAL",
"availabilityImpact": "HIGH",
"baseScore": 7.8,
"baseSeverity": "HIGH",
"confidentialityImpact": "HIGH",
"integrityImpact": "HIGH",
"privilegesRequired": "LOW",
"scope": "UNCHANGED",
"userInteraction": "NONE",
"vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
"version": "3.1"
},
"exploitabilityScore": 1.8,
"impactScore": 5.9,
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"type": "Secondary"
},
{
"cvssData": {
"attackComplexity": "LOW",
"attackVector": "LOCAL",
"availabilityImpact": "HIGH",
"baseScore": 7.8,
"baseSeverity": "HIGH",
"confidentialityImpact": "HIGH",
"integrityImpact": "HIGH",
"privilegesRequired": "LOW",
"scope": "UNCHANGED",
"userInteraction": "NONE",
"vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
"version": "3.1"
},
"exploitabilityScore": 1.8,
"impactScore": 5.9,
"source": "nvd@nist.gov",
"type": "Primary"
},
{
"cvssData": {
"attackComplexity": "LOW",
"attackVector": "LOCAL",
"availabilityImpact": "HIGH",
"baseScore": 7.8,
"baseSeverity": "HIGH",
"confidentialityImpact": "HIGH",
"integrityImpact": "HIGH",
"privilegesRequired": "LOW",
"scope": "UNCHANGED",
"userInteraction": "NONE",
"vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
"version": "3.1"
},
"exploitabilityScore": 1.8,
"impactScore": 5.9,
"source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c",
"type": "Secondary"
}
],
"ssvcV203": [
{
"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"ssvcData": {
"id": "CVE-2026-23111",
"options": [
{
"exploitation": "none"
},
{
"automatable": "no"
},
{
"technicalImpact": "total"
}
],
"role": "CISA Coordinator",
"timestamp": "2026-06-09T13:07:47.429787Z",
"version": "2.0.3"
}
}
]
},
"published": "2026-02-13T14:16:10.283",
"references": [
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"tags": [
"Patch"
],
"url": "https://git.kernel.org/stable/c/1444ff890b4653add12f734ffeffc173d42862dd"
},
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"tags": [
"Patch"
],
"url": "https://git.kernel.org/stable/c/42c574c1504aa089a0a142e4c13859327570473d"
},
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"tags": [
"Patch"
],
"url": "https://git.kernel.org/stable/c/8b68a45f9722f2babe9e7bad00aa74638addf081"
},
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"tags": [
"Patch"
],
"url": "https://git.kernel.org/stable/c/8c760ba4e36c750379d13569f23f5a6e185333f5"
},
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"tags": [
"Patch"
],
"url": "https://git.kernel.org/stable/c/b9b6573421de51829f7ec1cce76d85f5f6fbbd7f"
},
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"tags": [
"Patch"
],
"url": "https://git.kernel.org/stable/c/f41c5d151078c5348271ffaf8e7410d96f2d82f8"
},
{
"source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c",
"url": "https://access.redhat.com/errata/RHSA-2026:10108"
},
{
"source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c",
"url": "https://access.redhat.com/errata/RHSA-2026:10996"
},
{
"source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c",
"url": "https://access.redhat.com/errata/RHSA-2026:18134"
},
{
"source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c",
"url": "https://access.redhat.com/errata/RHSA-2026:62639"
},
{
"source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c",
"url": "https://access.redhat.com/errata/RHSA-2026:62641"
},
{
"source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c",
"url": "https://access.redhat.com/errata/RHSA-2026:6570"
},
{
"source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c",
"url": "https://access.redhat.com/errata/RHSA-2026:9112"
},
{
"source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c",
"url": "https://access.redhat.com/security/cve/CVE-2026-23111"
},
{
"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"url": "https://blog.exodusintel.com/2026/06/08/off-by-exploiting-a-use-after-free-in-the-linux-kernel/"
},
{
"source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c",
"url": "https://bugzilla.redhat.com/show_bug.cgi?id=2439687"
},
{
"source": "0b142b55-0307-4c5a-b3c9-f314f3fb7c5e",
"url": "https://cert-portal.siemens.com/productcert/html/ssa-019113.html"
},
{
"source": "0b142b55-0307-4c5a-b3c9-f314f3fb7c5e",
"url": "https://cert-portal.siemens.com/productcert/html/ssa-082556.html"
},
{
"source": "0b142b55-0307-4c5a-b3c9-f314f3fb7c5e",
"url": "https://cert-portal.siemens.com/productcert/html/ssa-253495.html"
},
{
"source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c",
"url": "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-23111.json"
}
],
"sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"vulnStatus": "Modified",
"weaknesses": [
{
"description": [
{
"lang": "en",
"value": "CWE-416"
}
],
"source": "nvd@nist.gov",
"type": "Primary"
},
{
"description": [
{
"lang": "en",
"value": "CWE-416"
}
],
"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"type": "Secondary"
},
{
"description": [
{
"lang": "en",
"value": "CWE-672"
}
],
"source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c",
"type": "Secondary"
}
]
},
"severity": "HIGH",
"source": "nvd",
"title": "In the Linux kernel, the following vulnerability has been resolved:\n\nnetfilter: nf_tables: fix inverted genmask check..."
}
Enrichment data
Aggregated bundle (all enrichments)