Description
In the Linux kernel, the following vulnerability has been resolved: netfilter: flowtable: hold reference on ct until flow is released nf_ct_put() releases the ct->ext area inmediately, the rcu typesafe semantics also allow to refer to the wrong conntrack from the flowtable datapath. Hold reference on ct until flow is released after rcu grace period. Add rcu_barrier() on module exit path, to ensure pending flow entries are release before module goes away.
References8
- git.kernel.org/stable/c/12c1ac230f4ca16e0017b62a963ab75e0b48074f
- git.kernel.org/stable/c/61c6688be282277c6e91ab286a7acd0ae8681ac6
- git.kernel.org/stable/c/8274cdc5f9c57e17ed77fc4ba76212536c840f25
- git.kernel.org/stable/c/93ff1594be1aad4da364462dd8db050ebcfda2de
- git.kernel.org/stable/c/a43cd2b67b91e943273c913237a7a88c50cdcfbc
- git.kernel.org/stable/c/d9e6175a3ee48209ee65f294fc567b4e16b29b74
- git.kernel.org/stable/c/e75a9fa1d44bcbd66ea02e8781bcca6ea4076e0d
- git.kernel.org/stable/c/eed6997e8dc40593a539fcc722e7ed51b18db86c
Metrics
- CVSS 3.1
-
7.8
HIGH
Score source: CNA
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H - EPSS — exploit probability
- 0% percentile: 3 · as of 10 November 2026
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