What’s Vulnerable › Vulnerabilities

CVE-2026-23403: apparmor: fix memory leak in verify_header

• Severity: medium (CVSS 5.5 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 0.2% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2026-04-01 · updated 2026-06-17
• Weakness: CWE-401

Description

In the Linux kernel, the following vulnerability has been resolved: apparmor: fix memory leak in verify_header The function sets `*ns = NULL` on every call, leaking the namespace string allocated in previous iterations when multiple profiles are unpacked. This also breaks namespace consistency checking since *ns is always NULL when the comparison is made. Remove the incorrect assignment. The caller (aa_unpack) initializes *ns to NULL once before the loop, which is sufficient.

Affected products

• Linux kernel: from 3.12.1 before 5.10.253; from 5.11 before 5.15.203; from 5.16 before 6.1.169; from 6.2 before 6.6.130; from 6.7 before 6.12.77; from 6.13 before 6.18.18 — fixed in 5.10.253, 5.15.203, 6.1.169, 6.12.77, 6.18.18, 6.19.8

How to fix

Upgrade to a fixed version: Linux kernel 5.10.253, 5.15.203, 6.1.169, 6.12.77. Check the vendor advisory for mitigations.

References

• https://git.kernel.org/stable/c/42fd831abfc15d0643c14688f0522556b347e7e6
• https://git.kernel.org/stable/c/4f0889f2df1ab99224a5e1ac4e20437eea5fe38e
• https://git.kernel.org/stable/c/663ce34786e759ebcbeb3060685c20bcc886d51a
• https://git.kernel.org/stable/c/6b79abcb3c985e153fcf9d395e1d4336081aabc2
• https://git.kernel.org/stable/c/786e2c2a87d9c505f33321d1fd23a176aa8ddeb1
• https://git.kernel.org/stable/c/9d678eb0fe55c9195d9a253e8c5b82a87b930737
• https://git.kernel.org/stable/c/bcf82c0c5a8b383fd2d5d8f3fd880cdcab2ac557
• https://git.kernel.org/stable/c/e38c55d9f834e5b848bfed0f5c586aaf45acb825

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