bit-zookeeper-2026-84501

{
  "affected": [
    {
      "package": {
        "ecosystem": "Bitnami",
        "name": "zookeeper",
        "purl": "pkg:bitnami/zookeeper"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "3.8.0"
            },
            {
              "fixed": "3.8.7"
            },
            {
              "introduced": "3.9.0"
            },
            {
              "fixed": "3.9.6"
            }
          ],
          "type": "SEMVER"
        }
      ],
      "severity": [
        {
          "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N",
          "type": "CVSS_V3"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2026-84501"
  ],
  "database_specific": {
    "cpes": [
      "cpe:2.3:a:apache:zookeeper:*:*:*:*:*:*:*:*"
    ],
    "severity": "Medium"
  },
  "details": "An unauthenticated attacker can inject arbitrary fake log lines into Apache ZooKeeper's operational log by sending a crafted add_auth(\"ensemble\", ...) request containing newline characters (\\n). When the ensemble name doesn't match, EnsembleAuthenticationProvider.handleAuthentication() logs the raw, unsanitized name via LOG.warn(). Because SLF4J's {} placeholder preserves embedded newlines, the attacker can forge complete log entries — with arbitrary timestamps, log levels, class names, and messages — that are visually indistinguishable from genuine ZooKeeper log output.\n\nThis issue affects Apache ZooKeeper: from 3.9.0 through 3.9.5, from 3.8.0 through 3.8.6.\n\nUsers are recommended to upgrade to version 3.8.7 or 3.9.6, which fixes the issue.",
  "id": "BIT-zookeeper-2026-84501",
  "modified": "2026-09-19T09:02:05.474Z",
  "published": "2026-09-19T08:51:30.697Z",
  "references": [
    {
      "type": "DISCUSSION",
      "url": "http://www.openwall.com/lists/oss-security/2026/09/15/7"
    },
    {
      "type": "ADVISORY",
      "url": "https://lists.apache.org/thread/ohby1g6zjt72p0w79rhbr41nczzvr33y"
    },
    {
      "type": "WEB",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-84501"
    }
  ],
  "schema_version": "1.6.2",
  "summary": "Apache ZooKeeper: Operational log forgery via newline injection in EnsembleAuthenticationProvider"
}