A heap-based buffer overflow flaw was found in the way the legacy_parse_param function in the Filesystem Context functionality of the Linux kernel verified the supplied parameters length. An unprivileged (in case of unprivileged user namespaces enabled, otherwise needs namespaced CAP_SYS_ADMIN privilege) local user able to open a filesystem that does not support the Filesystem Context API (and thus fallbacks to legacy handling) could use this flaw to escalate their privileges on the system.

CNA Affected

[
  {
    "product": "kernel",
    "vendor": "n/a",
    "versions": [
      {
        "status": "affected",
        "version": "8.4"
      }
    ]
  }
]