bit-libpython-2026-87910
bitnami_vulndb
Description
When tarfile extracts a link on a system that doesn't support links, it falls back to extracting a member from the archive. In this case, the filter function is run twice: once for the extracted member, and once with name set to the location of the link. For one of the calls, the return value was ignored. Instead, the member should be skipped if either call returns None.
Timeline
- Published
- unknown
- Last Modified
- unknown
CVSS Details
CVSS details not available.
Affected Products
No product information available.
References
- http://www.openwall.com/lists/oss-security/2026/09/11/8
- https://github.com/python/cpython/commit/d9565e54b1fc6d63c5be9afd58114499128fa57b
- https://github.com/python/cpython/commit/fb2f0bbc3b35264f09cc2cb2934b7987527a6bc2
- https://github.com/python/cpython/issues/157265
- https://github.com/python/cpython/pull/157266
- https://mail.python.org/archives/list/security-announce@python.org/thread/57TBTLL2W6APMZR3A25B2YV7GL3EPTDJ/
- https://nvd.nist.gov/vuln/detail/CVE-2026-87910
- https://github.com/python/cpython/commit/9c17bace90f88dfba6d0e2fe23c8e7ae35f83955
Linked Vulnerabilities
No linked vulnerabilities found.
{
"affected": [
{
"package": {
"ecosystem": "Bitnami",
"name": "libpython",
"purl": "pkg:bitnami/libpython"
},
"ranges": [
{
"events": [
{
"introduced": "0"
}
],
"type": "SEMVER"
}
],
"severity": [
{
"score": "CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:A/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X",
"type": "CVSS_V4"
}
]
}
],
"aliases": [
"CVE-2026-87910"
],
"database_specific": {
"cpes": [
"cpe:2.3:a:python:python:*:*:*:*:*:*:*:*"
],
"severity": "Medium"
},
"details": "When tarfile extracts a link on a system that doesn't support links, it falls back to extracting a member from the archive. In this case, the filter function is run twice: once for the extracted member, and once with name set to the location of the link. For one of the calls, the return value was ignored. Instead, the member should be skipped if either call returns None.",
"id": "BIT-libpython-2026-87910",
"modified": "2026-09-23T09:09:37.701Z",
"published": "2026-09-17T11:47:03.864Z",
"references": [
{
"type": "WEB",
"url": "http://www.openwall.com/lists/oss-security/2026/09/11/8"
},
{
"type": "WEB",
"url": "https://github.com/python/cpython/commit/d9565e54b1fc6d63c5be9afd58114499128fa57b"
},
{
"type": "WEB",
"url": "https://github.com/python/cpython/commit/fb2f0bbc3b35264f09cc2cb2934b7987527a6bc2"
},
{
"type": "WEB",
"url": "https://github.com/python/cpython/issues/157265"
},
{
"type": "WEB",
"url": "https://github.com/python/cpython/pull/157266"
},
{
"type": "WEB",
"url": "https://mail.python.org/archives/list/security-announce@python.org/thread/57TBTLL2W6APMZR3A25B2YV7GL3EPTDJ/"
},
{
"type": "WEB",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2026-87910"
},
{
"type": "WEB",
"url": "https://github.com/python/cpython/commit/9c17bace90f88dfba6d0e2fe23c8e7ae35f83955"
}
],
"schema_version": "1.6.2",
"summary": "tarfile hardlink fallback ignores custom extraction filter rejection via None"
}