CVE-2026-45884

In the Linux kernel, the following vulnerability has been resolved: apparmor: avoid per-cpu hold underflow in aa_get_buffer When aa_get_buffer() pulls from the per-cpu list it unconditionally decrements cache->hold. If hold reaches 0 while count is still non-zero, the unsigned decrement wraps to UINT_MAX. This keeps hold non-zero for a very long time, so aa_put_buffer() never returns buffers to the global list, which can starve other CPUs and force repeated kmalloc(aa_g_path_max) allocations. Guard the decrement so hold never underflows.

CVSS v3 5.5 MEDIUM

5.5^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 1.8 / Impact : 3.6

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://git.kernel.org/stable/c/202824a1f89a9786c20a3d646a7c88d223abb1b2	Patch
https://git.kernel.org/stable/c/4bcddd0f6b2e52b4c7b520e4d36a115caf5b7169	Patch
https://git.kernel.org/stable/c/640cf2f09575c9dc344b3f7be2498d31e3923ead	Patch
https://git.kernel.org/stable/c/80c334acc6d0bee8605a358a33e69b4aea1ffb92	Patch

Configurations

Configuration 1 (hide)

OR	cpe:2.3:o:linux:linux_kernel::::::::
	cpe:2.3:o:linux:linux_kernel::::::::
	cpe:2.3:o:linux:linux_kernel::::::::

History

No history.

Information

Published : 2026-05-27 14:17

Updated : 2026-06-25 21:12

NVD link : CVE-2026-45884

Mitre link : CVE-2026-45884

CVE.ORG link : CVE-2026-45884

JSON object : View

Products Affected

linux

linux_kernel

CWE

CWE-191

Integer Underflow (Wrap or Wraparound)

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