CVE-2023-53839: dccp: fix data-race around dp->dccps_mss_cache

Severity: unknown
Exploited in the wild: not listed in CISA KEV
EPSS: 0.3% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2025-12-09 · updated 2026-06-17

Description

In the Linux kernel, the following vulnerability has been resolved: dccp: fix data-race around dp->dccps_mss_cache dccp_sendmsg() reads dp->dccps_mss_cache before locking the socket. Same thing in do_dccp_getsockopt(). Add READ_ONCE()/WRITE_ONCE() annotations, and change dccp_sendmsg() to check again dccps_mss_cache after socket is locked.

Affected products

Linux kernel: 2.6.14 — fixed in 6.5

How to fix

Upgrade to a fixed version: Linux kernel 6.5. Check the vendor advisory for mitigations.

References

https://git.kernel.org/stable/c/162fa1e3cfb62aa780d7c40c8cccb6c2f8bef7c1
https://git.kernel.org/stable/c/2bdc7f272b3a110a4e1fdee6c47c8d20f9b20817
https://git.kernel.org/stable/c/67eebc7a9217f999b779d46fba5312a716f0dc1d
https://git.kernel.org/stable/c/6d701c95ee6463abcbb6da543060d6e444554135
https://git.kernel.org/stable/c/a47e598fbd8617967e49d85c49c22f9fc642704c
https://git.kernel.org/stable/c/a6ddc1c774874dc704f96a99d015dc759627bba7
https://git.kernel.org/stable/c/d1f38d313bdfc52fb2f662e66d0c60dd1cfe2384
https://git.kernel.org/stable/c/f239c9e1d98b313435481b4926e8bdd06197e4d8

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