Libsoup: out-of-bounds read in cookie date handling of libsoup http library (CVE-2025-11021)

Why this deserves its current priority

CVSS is 7.5. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.

Analysis status

Analysis pending evidence review

Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.

Affected scope and exposure questions

The current feed maps libsoup (generic). Check affected ranges and fixed versions before updating.

Mapped affected packages and fixed versions
Package	Affected range	Fixed version
libsoupgeneric	>=0 <=3.6.5	Not reported

Recommended response

Check inventory. Check lockfiles and deployed manifests for libsoup.
Review the reported fix. Source-reported workaround: Mitigation for this issue is either not available or the currently available options don’t meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to a widespread installation base, or stability. It is strongly recommended to apply vendor-supplied patches once available.

Evidence timeline and material changes

Published upstream
Sep 26, 2025
Evidence: source:cvelist:source_dates:source-dates:record
Source modified
Jun 29, 2026
Evidence: source:cvelist:source_dates:source-dates:record
First seen by HOL
Jun 25, 2026

Sources and claim methodology

Upstream source 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.

Quoted source text, attributed separately from HOL analysis.

Libsoup: out-of-bounds read in cookie date handling of libsoup http libraryCVE-2025-11021