CVE-2026-23269
Out-of-Bounds Read in Linux AppArmor DFA State Validation
Publication date: 2026-03-18
Last updated on: 2026-04-18
Assigner: kernel.org
Description
Description
CVSS Scores
EPSS Scores
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Meta Information
Affected Vendors & Products
| Vendor | Product | Version / Range |
|---|---|---|
| linux | linux_kernel | * |
| linux | linux_kernel | to 416baaa9-dc9f-4396-8d5f-8c081fb06d67 (exc) |
| linux | kernel | * |
| apparmor | apparmor | * |
Helpful Resources
Exploitability
| CWE ID | Description |
|---|---|
| CWE-UNKNOWN |
Attack-Flow Graph
AI Powered Q&A
Can you explain this vulnerability to me?
This vulnerability exists in the Linux kernel's AppArmor component, specifically in the function unpack_pdb. It involves the validation of DFA (Deterministic Finite Automaton) start states, which are read from untrusted data and used as indexes into DFA state tables.
If the start state value exceeds the number of states in the DFA, the function aa_dfa_next() will perform an out-of-bounds read on the DFA tables. This means the kernel reads memory outside the intended bounds, which can lead to undefined behavior or potential security issues.
The vulnerability is addressed by rejecting policies that contain out-of-bounds start states during the unpacking process, preventing the out-of-bounds read.
How can this vulnerability impact me? :
This vulnerability can cause the Linux kernel to read memory outside the intended bounds, which may lead to system instability or crashes.
Because the out-of-bounds read is triggered by untrusted data, it could potentially be exploited by an attacker to cause denial of service or to leak sensitive information from kernel memory.
How does this vulnerability affect compliance with common standards and regulations (like GDPR, HIPAA)?:
I don't know
How can this vulnerability be detected on my network or system? Can you suggest some commands?
I don't know
What immediate steps should I take to mitigate this vulnerability?
The vulnerability has been resolved by rejecting policies with out-of-bounds start states during unpacking. Therefore, to mitigate this vulnerability, you should update your Linux kernel to a version that includes this fix.