CVE-2026-10650

Description

A flaw has been found in warmcat libwebsockets up to 4.5.8. This issue affects the function lws_ssh_parse_plaintext of the file plugins/protocol_lws_ssh_base/sshd.c of the component SSH Protocol Handler. Executing a manipulation of the argument msg_len can lead to resource consumption. The attack may be launched remotely. The exploit has been published and may be used. This patch is called 3f9f0c6ecaf0e6f3f219d30632c5d1f2479d7498. A patch should be applied to remediate this issue.

Read the notes from the security team

Status

Show unmaintained releases

Package	Ubuntu Release	Status
libwebsockets	26.04 LTS resolute	Fixed 4.3.5-3ubuntu1.1
	25.10 questing	Ignored end of life, was needs-triage
	24.04 LTS noble	Fixed 4.3.3-1.1ubuntu0.1~esm2
	22.04 LTS jammy	Fixed 4.0.20-2ubuntu1.1+esm1
	20.04 LTS focal	Fixed 3.2.1-3ubuntu0.1~esm2
	18.04 LTS bionic	Not affected
	16.04 LTS xenial	Not affected

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Notes

shishirsub10

plugin ssh_base only introduced after bionic

Patch details

For informational purposes only. We recommend not to cherry-pick updates. How can I get the fixes?

Package	Patch details
libwebsockets	Upstream: https://libwebsockets.org/git/libwebsockets/commit?id=3f9f0c6ecaf0e6f3f219d30632c5d1f2479d7498

Severity score breakdown

CVSS version:

Base score 5.5 · Medium

Base metrics

Parameter	Value
Attack vector	Network
Attack complexity	Low
Attack requirements	None
Privileges required	None
User interaction	None
Vulnerable system - Confidentiality impact	None
Vulnerable system - Integrity impact	None
Vulnerable system - Availability impact	Low
Subsequent system - Confidentiality impact	None
Subsequent system - Integrity impact	None
Subsequent system - Availability impact	None

Scores

Parameter	Value
Base score	5.5 · Medium
Base + Threat score	-
Base + Environmental score	-
Base + Threat + Environmental score	-

Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:P

Base score 5.3 · Medium