CVE-2024-0646: Kernel: ktls overwrites readonly memory pages when using function splice with a ktls socket as destination

Severity: high (CVSS 7.8 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.3% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2024-01-17 · updated 2026-08-06
Weakness: CWE-787

Description

An out-of-bounds memory write flaw was found in the Linux kernel’s Transport Layer Security functionality in how a user calls a function splice with a ktls socket as the destination. This flaw allows a local user to crash or potentially escalate their privileges on the system.

Affected products

Linux kernel: from 4.20 before 5.4.267; from 5.5 before 5.10.208; from 5.11 before 5.15.147; from 5.16 before 6.1.69; from 6.2 before 6.6.7; 6.7-rc1, 6.7-rc2, 6.7-rc3, 6.7-rc4 — fixed in 5.10.208, 5.15.147, 5.4.267, 6.1.69, 6.6.7
Red Hat Enterprise Linux: 8.0, 9.0

How to fix

Upgrade to a fixed version: Linux kernel 5.10.208, 5.15.147, 5.4.267, 6.1.69. Check the vendor advisory for mitigations.

References

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