CVE-2026-85197
libsoup: libsoup: Heap use-after-free in libsoup HTTP/2 client on_data_read() via GOAWAY during body upload
Severity
ImportantRed Hat Product Security
CVSS 3.1
Review impact separately from score.
Published · September 3, 2026
Updated · October 23, 2026
Description
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.
Statement
This flaw only affects libsoup3. HTTP/2 client support was introduced in libsoup 3.x; the legacy libsoup 2.x library does not implement an HTTP/2 client and therefore does not contain the vulnerable code path.
CVSS score applicability
The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.
Mitigation
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.
CVSS / CWE
CVSS 3.1 · 7.6CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:H
CWE-416 · Use After Free