CVE-2026-90195
In the Linux kernel, the following vulnerability has been resolved: riscv, bpf: Fix missing sign-ext for signed 1-byte and 2-byte kfunc args On RV64, the ABI requires sign-extension for signed 1-byte and 2-byte kfunc args. However, the RV64 JIT currently does not perform sign-extension for such kfunc args. Before commit 7ce090afbf72 ("bpf: Infer zext_dst based on static register liveness analysis"), state pruning could potentially omit zero-extension of 32-bit subregisters, which inadvertently masked the above issue by making the args appear as if they had been properly sign-extended. After that commit, the problem is exposed, causing the kfunc_call/kfunc_call_test4 selftest to fail. Fix this by extending the existing sign-extension logic to handle signed 1-byte and 2-byte kfunc args as well.
Affected versions
Linux kernel versions
6.9
and later are affected. Fixed in
6.12.110,
6.18.52,
7.2.6,
7.3-rc1
and their respective stable series.
References
4 totalFrequently asked questions
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What is CVE-2026-90195?
CVE-2026-90195 is a unscored severity Linux kernel vulnerability . It affects Linux kernel versions from 6.9 onward and has been patched in 6.12.110, 6.18.52, 7.2.6 and others. CVE-2026-90195 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.
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Is there a patch available for CVE-2026-90195?
Yes. CVE-2026-90195 has been patched. Fixed versions include 6.12.110, 6.18.52, 7.2.6 and others. If you are running Linux kernel 6.9 or later up to the fix versions, apply the relevant patch for your kernel branch.
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Is CVE-2026-90195 actively exploited?
No. CVE-2026-90195 has not been confirmed as actively exploited. It is not listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.