What’s Vulnerable › Vulnerabilities

CVE-2026-23223: xfs: fix UAF in xchk_btree_check_block_owner

• Severity: high (CVSS 7.8 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 0.1% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2026-02-18 · updated 2026-06-17
• Weakness: CWE-416

Description

In the Linux kernel, the following vulnerability has been resolved: xfs: fix UAF in xchk_btree_check_block_owner We cannot dereference bs->cur when trying to determine if bs->cur aliases bs->sc->sa.{bno,rmap}_cur after the latter has been freed. Fix this by sampling before type before any freeing could happen. The correct temporal ordering was broken when we removed xfs_btnum_t.

Affected products

• Linux kernel: from 6.9 before 6.12.72; from 6.13 before 6.18.11; from 6.19 before 6.19.1 — fixed in 6.12.72, 6.18.11, 6.19.1

How to fix

Upgrade to a fixed version: Linux kernel 6.12.72, 6.18.11, 6.19.1. Check the vendor advisory for mitigations.

References

• https://git.kernel.org/stable/c/1c253e11225bc5167217897885b85093e17c2217
• https://git.kernel.org/stable/c/1d411278dda293a507cb794db7d9ed3511c685c6
• https://git.kernel.org/stable/c/ba5264610423d9653aa36920520902d83841bcfd
• https://git.kernel.org/stable/c/ed82e7949f5cac3058f4100f3cd670531d41a266

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