CVE-2026-93261

Description

In the Linux kernel, the following vulnerability has been resolved: locking/lockdep: Fix NULL pointer dereference in __lock_set_class() register_lock_class() can return NULL when the lock class pool is exhausted, graph_lock() fails, or key validation fails. However, __lock_set_class() uses the return value directly in pointer arithmetic without a NULL check: class = register_lock_class(lock, subclass, 0); hlock->class_idx = class - lock_classes; If class is NULL, this computes a wild offset that corrupts hlock->class_idx. The subsequent reacquire_held_locks() call will invoke hlock_class() with this corrupted index, leading to a NULL or out-of-bounds pointer dereference. Add the missing NULL check, consistent with how __lock_acquire() already handles this case at the same call site.

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EPSS — Exploit Prediction

0.0020

Probability of exploitation

0.09%

Percentile rank

EPSS estimates the probability that this vulnerability will be exploited in the wild within the next 30 days. A higher score means more likely to be exploited.

References

Other References

https://git.kernel.org/stable/c/59a5c7dd331a3dab48100e1ef8e9bb4f9132a2b2 https://git.kernel.org/stable/c/5c3bff6cf26e6a54fbf8b893a879c32824d2d50d https://git.kernel.org/stable/c/7577e00b9ab506202b9f1a33de3cc8cc6413a4db https://git.kernel.org/stable/c/9be10f49dfc2e4b472b3a5f346483b67374774b8 https://git.kernel.org/stable/c/b2113dcd8238bf00ce37a34e67b29cf31d32a545 https://git.kernel.org/stable/c/e7c69c6695d84220847cca62a45e879e71e79e9d https://git.kernel.org/stable/c/f56e54fd24f05e9de528fcb77f6084f80c8066ce https://git.kernel.org/stable/c/f6093ff67ea6e347574819ed23e96e0f82a25ffc

Frequently Asked Questions

What is CVE-2026-93261? +

In the Linux kernel, the following vulnerability has been resolved: locking/lockdep: Fix NULL pointer dereference in __lock_set_class() register_lock_class() can return NULL when the lock class pool is exhausted, graph_lock() fails, or key validation fails. However, __lock_set_class() uses the return value directly in pointer arithmetic without a NULL check: class = register_lock_class(lock, subclass, 0); hlock->class_idx = class - lock_classes; If class is NULL, this computes a wild offset that corrupts hlock->class_idx. The subsequent reacquire_held_locks() call will invoke hlock_class() with this corrupted index, leading to a NULL or out-of-bounds pointer dereference. Add the missing NULL check, consistent with how __lock_acquire() already handles this case at the same call site.

How do I check if I'm vulnerable to CVE-2026-93261? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.