Vulnerability in Linux

CVE-2026-23403

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.

EPSS: 0.002 (7.5th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 5.5 (Medium). Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H.

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-23403?
CVE-2026-23403 is a medium-severity vulnerability in Linux, classified under Missing Release of Memory after Effective Lifetime. CVSS score: 5.5/10. Published 2026-04-01.
How severe is CVE-2026-23403?
Medium severity. CVSS v3 base score is 5.5 out of 10.