# CVE-2025-12105: Libsoup: heap use-after-free in libsoup message queue handling during http/2 read completion

Status: published. Published: 2025-10-23. Updated: 2026-11-05.

A flaw was found in the asynchronous message queue handling of the libsoup library, widely used by GNOME and WebKit-based applications to manage HTTP/2 communications. When network operations are aborted at specific timing intervals, an internal message queue item may be freed twice due to missing state synchronization. This leads to a use-after-free memory access, potentially crashing the affected application. Attackers could exploit this behavior remotely by triggering specific HTTP/2 read and cancel sequences, resulting in a denial-of-service condition.

## Remediation

- 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. (source: CNA: redhat)

## Affected products and versions

- GNOME / libsoup (libsoup): ≥ 0; ≤ 3.6.5 (affected, semver). Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 10 (libsoup3): ≥ 0:3.6.5-3.el10_1.7; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 10.0 Extended Update Support (libsoup3): ≥ 0:3.6.5-3.el10_0.10; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 6 (libsoup): Version range not reported. Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 7 (libsoup): Version range not reported. Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 8 (libsoup): Version range not reported. Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 9 (libsoup): Version range not reported. Source: CNA: redhat

## Severity and prioritization

- CVSS 3.1: 7.5 (high); CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H; source: CNA: redhat

- CISA KEV: No listing in collected sources

- EPSS: 0.46% as of 2026-11-05; percentile 39.75%

- SSVC: exploitation none; automatable yes; technical impact partial; source ADP: CISA-ADP

- Weaknesses: CWE-416

## Exploit evidence

No exploit evidence in collected sources. This is not proof of no exploitation.

## References

- https://access.redhat.com/errata/RHSA-2025:23139 (CNA: redhat; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/errata/RHSA-2025:23437 (CNA: redhat; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/security/cve/CVE-2025-12105 (CNA: redhat; vdb-entry, x_refsource_REDHAT)

- https://bugzilla.redhat.com/show_bug.cgi?id=2405992 (CNA: redhat; issue-tracking, x_refsource_REDHAT)

- https://gitlab.gnome.org/GNOME/libsoup/-/merge_requests/481 (CNA: redhat)

## Provenance

- CNA: redhat: https://www.cve.org/CVERecord?id=CVE-2025-12105; retrieved 2026-11-05; source updated 2026-11-05

- FIRST EPSS: https://api.first.org/data/v1/epss?cve=CVE-2025-12105; retrieved 2026-11-05; source updated Not reported

Revision: df91087dfcfb231bcb15e4fd6203a1f9c06d2a3cc15d8bd29a393cc9c23936a5

Canonical: https://y2.dev/cve/CVE-2025-12105

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