CVE-2023-53698: In the Linux kernel, the following vulnerability has been resolved: xsk: fix refcount underflow in error path Fix a refcount underflow problem repor...

Description

In the Linux kernel, the following vulnerability has been resolved: xsk: fix refcount underflow in error path Fix a refcount underflow problem reported by syzbot that can happen when a system is running out of memory. If xp_alloc_tx_descs() fails, and it can only fail due to not having enough memory, then the error path is triggered. In this error path, the refcount of the pool is decremented as it has incremented before. However, the reference to the pool in the socket was not nulled. This means that when the socket is closed later, the socket teardown logic will think that there is a pool attached to the socket and try to decrease the refcount again, leading to a refcount underflow. I chose this fix as it involved adding just a single line. Another option would have been to move xp_get_pool() and the assignment of xs->pool to after the if-statement and using xs_umem->pool instead of xs->pool in the whole if-statement resulting in somewhat simpler code, but this would have led to much more churn in the code base perhaps making it harder to backport.

Metrics

EPSS Probability

0.19%

9.4th percentile

Probability of exploitation in the next 30 days. Learn more

References

Timeline

Published: Oct 22, 2025
Last Modified: Jun 17, 2026
Status: Deferred

Frequently Asked Questions

What is CVE-2023-53698?

In the Linux kernel, the following vulnerability has been resolved: xsk: fix refcount underflow in error path Fix a refcount underflow problem reported by syzbot that can happen when a system is running out of memory. If xp_alloc_tx_descs() fails, and it can only fail due to not having enough memory, then the error path is triggered. In this error path, the refcount of the pool is decremented as it has incremented before. However, the reference to the pool in the socket was not nulled. This means that when the socket is closed later, the socket teardown logic will think that there is a pool attached to the socket and try to decrease the refcount again, leading to a refcount underflow. I chose this fix as it involved adding just a single line. Another option would have been to move xp_get_pool() and the assignment of xs->pool to after the if-statement and using xs_umem->pool instead of xs->pool in the whole if-statement resulting in somewhat simpler code, but this would have led to much more churn in the code base perhaps making it harder to backport.

How severe is CVE-2023-53698?

Severity scoring for CVE-2023-53698 is pending analysis. The EPSS model estimates a 0.19% probability of exploitation in the next 30 days.

How do I fix CVE-2023-53698?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.