CVE-2025-11021

Publication date 26 September 2025

Last updated 11 December 2025

Ubuntu priority

Cvss 3 Severity Score

Description

A flaw was found in the cookie date handling logic of the libsoup HTTP library, widely used by GNOME and other applications for web communication. When processing cookies with specially crafted expiration dates, the library may perform an out-of-bounds memory read. This flaw could result in unintended disclosure of memory contents, potentially exposing sensitive information from the process using libsoup.

Read the notes from the security team

Status

Show unmaintained releases

Package	Ubuntu Release	Status
libsoup3	25.10 questing	Fixed 3.6.5-3
	25.04 plucky	Fixed 3.6.5-1ubuntu0.2
	24.04 LTS noble	Fixed 3.4.4-5ubuntu0.5
	22.04 LTS jammy	Fixed 3.0.7-0ubuntu1+esm5
libsoup2.4	25.10 questing	Fixed 2.74.3-10.1ubuntu4
	25.04 plucky	Fixed 2.74.3-10ubuntu0.4
	24.04 LTS noble	Fixed 2.74.3-6ubuntu1.6
	22.04 LTS jammy	Fixed 2.74.2-3ubuntu0.6
	20.04 LTS focal	Fixed 2.70.0-1ubuntu0.5+esm1
	18.04 LTS bionic	Fixed 2.62.1-1ubuntu0.4+esm6
	16.04 LTS xenial	Fixed 2.52.2-1ubuntu0.3+esm5

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Notes

hlibk

This CVE has an identical fix to CVE-2025-4945

Patch details

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

Package	Patch details
libsoup3	Upstream: https://gitlab.gnome.org/GNOME/libsoup/-/merge_requests/473

Severity score breakdown

Parameter	Value
Base score	7.5 · High
Attack vector	Network
Attack complexity	Low
Privileges required	None
User interaction	None
Scope	Unchanged
Confidentiality	High
Integrity impact	None
Availability impact	None
Vector	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N