CVE-2026-80586

mptcp: options: reset DSS fields in case of unexpected size

State: Published
Severity: 9.8 Critical
Published: Aug 26, 2026
Updated: Oct 16, 2026
Reserved: Aug 26, 2026

Description

In the Linux kernel, the following vulnerability has been resolved:

mptcp: options: reset DSS fields in case of unexpected size

A remote peer could send a malformed DSS with a wrong size, followed by another DSS or MPC + Data. In this case, the first suboption will be ignored, but leaving some fields written, which could lead to inconsistency or access uninitialized data.

Explicitly reset the fields that could have been modified in case of unexpected size.

Scores

CVSS	Score	Vector	Source
3.1	9.8 Critical	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H	Linux

Weaknesses

The record names no weakness.

Affected Products

Product	Versions
LinuxLinux	648ef4b88673dadb8463bf0d4b10fbf33d55def8 to before 15e35fdad7a5576bf3f1c8d688877aeb5d1b506bAffected 648ef4b88673dadb8463bf0d4b10fbf33d55def8 to before b1256090816ec46011601e084be580731df58fc7Affected 648ef4b88673dadb8463bf0d4b10fbf33d55def8 to before 192878df582c51d440bf7b91a15f297f29f2b596Affected 648ef4b88673dadb8463bf0d4b10fbf33d55def8 to before 26dac5c9ffb20812b475fdf253eb04fab99cff3bAffected 648ef4b88673dadb8463bf0d4b10fbf33d55def8 to before 4e80eff5c1c893aca2ac1d202f0b256d2e52ecdeAffected 648ef4b88673dadb8463bf0d4b10fbf33d55def8 to before 1fade1b2ac5b1a4948e538fae7313bea57b5ac36Affected 648ef4b88673dadb8463bf0d4b10fbf33d55def8 to before 27ed642a4e7e4b5df4b8522c72c457a67e052493Affected 648ef4b88673dadb8463bf0d4b10fbf33d55def8 to before 35772b4981f38ba8059372cde8753e8e477e98ecAffected
LinuxLinux	5.6Affected before 5.6Not affected 5.10.266 through 5.10.Not affected 5.15.217 through 5.15.Not affected 6.1.184 through 6.1.Not affected 6.6.153 through 6.6.Not affected 6.12.105 through 6.12.Not affected 6.18.46 through 6.18.Not affected 7.1.10 through 7.1.*Not affected 7.2 and laterNot affected

Product

Versions

LinuxLinux

648ef4b88673dadb8463bf0d4b10fbf33d55def8 to before 15e35fdad7a5576bf3f1c8d688877aeb5d1b506bAffected
648ef4b88673dadb8463bf0d4b10fbf33d55def8 to before b1256090816ec46011601e084be580731df58fc7Affected
648ef4b88673dadb8463bf0d4b10fbf33d55def8 to before 192878df582c51d440bf7b91a15f297f29f2b596Affected
648ef4b88673dadb8463bf0d4b10fbf33d55def8 to before 26dac5c9ffb20812b475fdf253eb04fab99cff3bAffected
648ef4b88673dadb8463bf0d4b10fbf33d55def8 to before 4e80eff5c1c893aca2ac1d202f0b256d2e52ecdeAffected
648ef4b88673dadb8463bf0d4b10fbf33d55def8 to before 1fade1b2ac5b1a4948e538fae7313bea57b5ac36Affected
648ef4b88673dadb8463bf0d4b10fbf33d55def8 to before 27ed642a4e7e4b5df4b8522c72c457a67e052493Affected
648ef4b88673dadb8463bf0d4b10fbf33d55def8 to before 35772b4981f38ba8059372cde8753e8e477e98ecAffected

LinuxLinux

5.6Affected
before 5.6Not affected
5.10.266 through 5.10.*Not affected
5.15.217 through 5.15.*Not affected
6.1.184 through 6.1.*Not affected
6.6.153 through 6.6.*Not affected
6.12.105 through 6.12.*Not affected
6.18.46 through 6.18.*Not affected
7.1.10 through 7.1.*Not affected
7.2 and laterNot affected

References

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