# CVE-2026-85197: Libsoup: libsoup: heap use-after-free in libsoup http/2 client on_data_read() via goaway during body upload

Status: published. Published: 2026-09-04. Updated: 2026-11-04.

A flaw was found in libsoup. A malicious HTTP/2 server or a Man-in-the-Middle (MITM) attacker can exploit a heap use-after-free vulnerability in the HTTP/2 client implementation. This occurs when a GNOME application uploads a file using HTTP/2, and the server sends a GOAWAY frame while the file body is being read asynchronously. This can lead to memory corruption, potentially resulting in information disclosure or arbitrary code execution.

## Remediation

- workaround: Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base, or stability. (source: CNA: redhat)

## Affected products and versions

- Red Hat / Red Hat Enterprise Linux 10 (libsoup3): ≥ 0:3.6.5-3.el10_2.14; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 10.0 Extended Update Support (libsoup3): ≥ 0:3.6.5-3.el10_0.18; < * (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: 7.6 (high); CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:H; source: CNA: redhat

- CISA KEV: No listing in collected sources

- EPSS: 0.34% as of 2026-11-04; percentile 27.08%

- SSVC: exploitation poc; automatable no; technical impact partial; source ADP: CISA-ADP

- Weaknesses: CWE-416

## Exploit evidence

- exploit: https://gitlab.gnome.org/GNOME/libsoup/-/work_items/552 (ADP: CISA-ADP)

## References

- https://access.redhat.com/errata/RHSA-2026:68235 (CNA: redhat; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/errata/RHSA-2026:82728 (CNA: redhat; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/security/cve/CVE-2026-85197 (CNA: redhat; vdb-entry, x_refsource_REDHAT)

- https://bugzilla.redhat.com/show_bug.cgi?id=2528425 (CNA: redhat; issue-tracking, x_refsource_REDHAT)

- https://gitlab.gnome.org/GNOME/libsoup/-/work_items/552 (CNA: redhat)

- https://gitlab.gnome.org/GNOME/libsoup/-/work_items/552 (ADP: CISA-ADP; exploit)

## Provenance

- CNA: redhat: https://www.cve.org/CVERecord?id=CVE-2026-85197; retrieved 2026-11-05; source updated 2026-11-04

- FIRST EPSS: https://api.first.org/data/v1/epss?cve=CVE-2026-85197; retrieved 2026-11-05; source updated Not reported

Revision: c3a41b52bf4b9914abff1b5a5d74f6f76dab93565ccdb5e9f0ed9193b5b97535

Canonical: https://y2.dev/cve/CVE-2026-85197

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