CVE-2025-39990
Published Oct 15, 2025
Modified Apr 15, 2026
Description
In the Linux kernel, the following vulnerability has been resolved: bpf: Check the helper function is valid in get_helper_proto kernel test robot reported verifier bug [1] where the helper func pointer could be NULL due to disabled config option. As Alexei suggested we could check on that in get_helper_proto directly. Marking tail_call helper func with BPF_PTR_POISON, because it is unused by design. [1] https://lore.kernel.org/oe-lkp/[email protected]
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References
Frequently Asked Questions
What is CVE-2025-39990? +
In the Linux kernel, the following vulnerability has been resolved:
bpf: Check the helper function is valid in get_helper_proto
kernel test robot reported verifier bug [1] where the helper func
pointer could be NULL due to disabled config option.
As Alexei suggested we could check on that in get_helper_proto
directly. Marking tail_call helper func with BPF_PTR_POISON,
because it is unused by design.
[1] https://lore.kernel.org/oe-lkp/[email protected]
How do I check if I'm vulnerable to CVE-2025-39990? +
You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.