CVE-2026-6324

Publication date 29 May 2026

Last updated 30 September 2026

Ubuntu priority

Cvss 3 Severity Score

Description

A flaw was found in libsoup. A remote attacker could exploit an unsigned to signed conversion error in the `soup_body_input_stream_read_chunked()` function by sending a malicious HTTP request. This vulnerability occurs when libsoup operates behind a non-libsoup proxy server or as a proxy in front of a non-libsoup backend server. Successful exploitation can allow an attacker to bypass security controls, poison web caches, or gain unauthorized access.

Status

Show unmaintained releases

Package	Ubuntu Release	Status
libsoup2.4	26.04 LTS resolute	Ignored changes too intrusive
	25.10 questing	Ignored end of life, was needs-triage
	24.04 LTS noble	Ignored changes too intrusive
	22.04 LTS jammy	Ignored changes too intrusive
	20.04 LTS focal	Ignored changes too intrusive
	18.04 LTS bionic	Ignored changes too intrusive
	16.04 LTS xenial	Ignored changes too intrusive
libsoup3	26.04 LTS resolute	Vulnerable
	25.10 questing	Ignored end of life, was needs-triage
	24.04 LTS noble	Vulnerable
	22.04 LTS jammy	Vulnerable

Patch details

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

Package	Patch details
libsoup2.4	Upstream: 96ac392
libsoup3	Upstream: 96ac392

Severity score breakdown

CVSS version: CVSS v3.0

Base score 4.8 · Medium

Base metrics

Parameter	Value
Attack vector	Network
Attack complexity	High
Privileges required	None
User interaction	None
Scope	Unchanged
Confidentiality impact	Low
Integrity impact	Low
Availability impact	None

Scores

Parameter	Value
Base score	4.8 · Medium
Exploitability score	-
Impact score	-

Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N