Vulnerability in Linux
CVE-2025-39926
In the Linux kernel, the following vulnerability has been resolved: genetlink: fix genl_bind() invoking bind() after -EPERM Per family bind/unbind callbacks were introduced to allow families to track multicast group consumer presence, e.g. to start or stop producing events depending on listeners. However, in genl_bind() the bind() callback was invoked even if capability checks failed and ret was set to -EPERM. This means that callbacks could run on behalf of unauthorized callers while the syscall still returned failure to user space. Fix this by only invoking bind() after "if (ret) break;" check i.e. after permission checks have succeeded.
EPSS: 0.001 (3.3th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 5.5 (Medium). Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H.
Affected products
- Linux — versions 3de21a8990d3c2cc507e9cc4ed00f36358d5b93e, 6.9, 0
- Linux Linux_kernel — versions 6.17
References
Frequently asked questions
- What is CVE-2025-39926?
- CVE-2025-39926 is a medium-severity vulnerability in Linux. CVSS score: 5.5/10. Published 2025-10-01.
- How severe is CVE-2025-39926?
- Medium severity. CVSS v3 base score is 5.5 out of 10.