# CVE-2026-85197: GNOME libsoup heap use-after-free in HTTP/2 client

Source: https://junglewise.ai/threats/cve-2026-85197-gnome-libsoup-heap-use-after-free-in-http-2-client  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-09-04. Updated: 2026-09-26  
License: CC BY 4.0 with a link back

CVE-2026-85197 · Severity: high · CVSS 7.6 · Published 2026-09-04

libsoup is an HTTP library used by GNOME applications to communicate with web servers. A malicious HTTP/2 server or network attacker can trigger a memory corruption vulnerability when a file upload is interrupted with a GOAWAY frame, potentially leading to sensitive data exposure or complete compromise of the affected application.

Technologies: [Gnome Libsoup](https://junglewise.ai/threats/technologies/libsoup). Vendors: [Gnome](https://junglewise.ai/threats/vendors/gnome).

## Quick answers

**Is CVE-2026-85197 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-85197 being exploited in the wild.

**How severe is CVE-2026-85197?** High severity, with a CVSS score of 7.6, published 4 September 2026.

**Which products and versions are affected?** Gnome Libsoup <unknown.

**Is there a fix for CVE-2026-85197?** No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.

**How is CVE-2026-85197 attacked?** It is attacked over the network or from the adjacent network.

**Am I affected by CVE-2026-85197?** Check whether you run Gnome Libsoup at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## Technical details

A heap use-after-free vulnerability exists in libsoup's HTTP/2 client implementation within the on_data_read() function. The flaw is triggered when a server sends a GOAWAY frame while the HTTP/2 client is asynchronously reading a file body during upload. This results in memory being freed and subsequently accessed, causing memory corruption. An attacker controlling an HTTP/2 server or performing a man-in-the-middle (MITM) attack on the network can exploit this condition to achieve information disclosure or arbitrary code execution. A patch is available in libsoup3 as of September 2026.

## Affected products

- GNOME libsoup <unknown

## Timeline

- 2026-09-04: disclosed
- 2026-09-16: advisory: Red Hat RHSA-2026:68235 issued for libsoup3 in Red Hat Enterprise Linux 10

## References

- [https://access.redhat.com/downloads/content/package-browser/](https://access.redhat.com/downloads/content/package-browser/)
- [https://access.redhat.com/errata/RHSA-2026:68235](https://access.redhat.com/errata/RHSA-2026:68235)

## Related threats

- [libsoup HTTP request smuggling via undrained Expect: 100-continue body](https://junglewise.ai/threats/cve-2026-103399-a-flaw-was-found-in-soupserver-libsoup-when-an-http-1-x-client)
- [libsoup heap buffer overflow in permessage-deflate WebSocket extension](https://junglewise.ai/threats/cve-2026-102560-a-flaw-was-found-in-libsoup-when-the-permessage-deflate)
- [libsoup heap buffer overflow in WebSocket handling](https://junglewise.ai/threats/cve-2026-102558-a-flaw-was-found-in-libsoup-when-max-incoming-payload-size-is)
- [libsoup out-of-bounds read in data-URI base64 decoding](https://junglewise.ai/threats/cve-2026-102555-a-flaw-was-found-in-libsoup-the-soup-uri-decode-data-uri)
- [libsoup heap corruption in WebSocket message reassembly](https://junglewise.ai/threats/cve-2026-102557-a-flaw-was-found-in-libsoup-when-reassembling-fragmented)