What’s Vulnerable › Vulnerabilities

CVE-2026-43074: eventpoll: defer struct eventpoll free to RCU grace period

• Severity: high (CVSS 7.8 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 0.5% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2026-05-06 · updated 2026-10-19
• Weakness: CWE-401

Description

In the Linux kernel, the following vulnerability has been resolved: eventpoll: defer struct eventpoll free to RCU grace period In certain situations, ep_free() in eventpoll.c will kfree the epi->ep eventpoll struct while it still being used by another concurrent thread. Defer the kfree() to an RCU callback to prevent UAF.

Affected products

• Linux kernel: from 6.4.1 before 6.6.136; from 6.7 before 6.12.83; from 6.13 before 6.18.24; from 6.19 before 6.19.14; 6.4, 7.0-rc1, 7.0-rc2, 7.0-rc3, 7.0-rc4, 7.0-rc5 (+2) — fixed in 6.12.83, 6.18.24, 6.19.14, 6.6.136

How to fix

Upgrade to a fixed version: Linux kernel 6.12.83, 6.18.24, 6.19.14, 6.6.136. Check the vendor advisory for mitigations.

References

• https://git.kernel.org/stable/c/07712db80857d5d09ae08f3df85a708ecfc3b61f
• https://git.kernel.org/stable/c/5b1173b165421561db29f30afc7e97d940a398a9
• https://git.kernel.org/stable/c/7e8083f5eeedab0f460063b9c2c14c9a4e71a427
• https://git.kernel.org/stable/c/902120be4f44947df6311002addc7faf69bdbff1
• https://git.kernel.org/stable/c/a6566cd33f6f967a7651ebf2ce0dd31572e319cf
• https://git.kernel.org/stable/c/a6d57084372161f86660bc4607784420e00efe2c
• https://git.kernel.org/stable/c/ae0bb9c1fb7c2594519aeeb096cf2c3b7837b322
• https://cert-portal.siemens.com/productcert/html/ssa-784472.html

Get alerted when CVE-2026-43074 or the next vulnerability affects your stack