Description
In the Linux kernel, the following vulnerability has been resolved: netfilter: xt_hashlimit: validate hashtable supports XT_HASHLIMIT_RATE_MATCH The XT_HASHLIMIT_RATE_MATCH flag mode changes the semantics of the dsthash_ent structure which represents an entry in the hashtable. There is a union area which uses a different layout to express the rate match mode. Update .checkentry path to validate the XT_HASHLIMIT_RATE_MATCH mode flag is requested by two or more different rules that refer to the same hashtable. Otherwise, uninitialized access to the burst field in the union is possible. Reject the use of the XT_HASHLIMIT_RATE_MATCH mode flag if set on by revision less than 3 too.
References8
- git.kernel.org/stable/c/06a76334243ccd875a981aa8bb46c0f931ef1e3b
- git.kernel.org/stable/c/24683fea1f06bd3bd2707b99460e859bc6464c22
- git.kernel.org/stable/c/305b63e1402267459fdabb183af4527f6799eebf
- git.kernel.org/stable/c/32ec8d4aba2cf22e12bdc28df8c4bd833c195fc0
- git.kernel.org/stable/c/402befce5854c195058cf4bab7c78ca286068a26
- git.kernel.org/stable/c/d186f77d18bdfb252d401ff992ca3001a6a65a0f
- git.kernel.org/stable/c/dee686b5e7f21180538ff719867702f411c8eb5c
- git.kernel.org/stable/c/f76ab783e7d8d33e33dd7dfa697297f70d57b0e8
Metrics
- CVSS 3.1
-
7.1
HIGH
Score source: CNA
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N - EPSS — exploit probability
- 0% percentile: 2 · as of 11 November 2026
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