CVE-2025-21966: dm-flakey: Fix memory corruption in optional corrupt_bio_byte feature

Severity: high (CVSS 7.8 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.2% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2025-04-01 · updated 2026-06-17
Weakness: CWE-787

Description

In the Linux kernel, the following vulnerability has been resolved: dm-flakey: Fix memory corruption in optional corrupt_bio_byte feature Fix memory corruption due to incorrect parameter being passed to bio_init

Affected products

Linux kernel: from 6.5 before 6.6.84; from 6.7 before 6.12.20; from 6.13 before 6.13.8; 6.14-rc1, 6.14-rc2, 6.14-rc3, 6.14-rc4, 6.14-rc5, 6.14-rc6 — fixed in 6.12.20, 6.13.8, 6.6.84

How to fix

Upgrade to a fixed version: Linux kernel 6.12.20, 6.13.8, 6.6.84. Check the vendor advisory for mitigations.

References

https://git.kernel.org/stable/c/57e9417f69839cb10f7ffca684c38acd28ceb57b
https://git.kernel.org/stable/c/5a87e46da2418c57b445371f5ca0958d5779ba5f
https://git.kernel.org/stable/c/818330f756f3800c37d738bd36bce60eac949938
https://git.kernel.org/stable/c/da070843e153471be4297a12fdaa64023276f40e

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