CVE-2026-90327
Published Sep 17, 2026
Description
In the Linux kernel, the following vulnerability has been resolved: phonet: pep: do not write beyond optlen in getsockopt pep_getsockopt() clamps the reported length to the caller's buffer with min_t(), but then stores the value with put_user(val, (int __user *) optval), which always writes sizeof(int) bytes. A getsockopt() call with an optlen smaller than sizeof(int) thus reports the clamped length yet writes a full int, one to three bytes past the user buffer. Write the value with copy_to_user() bounded by len, so at most optlen bytes are copied, matching the length reported back to userspace.
Is your site exposed to CVE-2026-90327?
Run a free security scan — no signup, results in seconds.
References
Other References
https://git.kernel.org/stable/c/056eea1a2068ad2fb7c3093c5f1095268f87d0c7
https://git.kernel.org/stable/c/1bf499e438da80455e258049bce60ffb3a53f3fa
https://git.kernel.org/stable/c/6054fed6bad08b6d03973e8ffca7f0c9394d1c30
https://git.kernel.org/stable/c/77e5eb0e192aec6710c03ca8144582fd2af36ca4
https://git.kernel.org/stable/c/95e0ed2439dd1792eb454c68ae8d10f30ffe3bff
https://git.kernel.org/stable/c/c4487e4d5309de587479ecc2f5173b49586f46f4
https://git.kernel.org/stable/c/eac733a0b6fe0a52d91f9f623425735ed50ac6c2
https://git.kernel.org/stable/c/f97022fefe6eb06ee18549d603420440f2959802
Frequently Asked Questions
What is CVE-2026-90327? +
In the Linux kernel, the following vulnerability has been resolved:
phonet: pep: do not write beyond optlen in getsockopt
pep_getsockopt() clamps the reported length to the caller's buffer with
min_t(), but then stores the value with put_user(val, (int __user *)
optval), which always writes sizeof(int) bytes. A getsockopt() call with
an optlen smaller than sizeof(int) thus reports the clamped length yet
writes a full int, one to three bytes past the user buffer.
Write the value with copy_to_user() bounded by len, so at most optlen
bytes are copied, matching the length reported back to userspace.
How do I check if I'm vulnerable to CVE-2026-90327? +
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.