Quick answers
- Is CVE-2026-15711 exploited in the wild?
- No. Junglewise Threat Intelligence has no report of CVE-2026-15711 being exploited in the wild.
- How severe is CVE-2026-15711?
- High severity, with a CVSS score of 7.5, published 14 July 2026.
- Which products and versions are affected?
- Gnome Libsoup Red Hat Enterprise Linux 10.
- Is there a fix for CVE-2026-15711?
- 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-2026-15711 attacked?
- It is attacked over the network, in a software library.
- Am I affected by CVE-2026-15711?
- 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 vulnerability exists in libsoup's WebSocket frame parsing implementation within `soup-websocket-connection.c`. Per RFC 6455 §5.5, control frames (PING, PONG, CLOSE) must not exceed a payload of 125 bytes. While libsoup's send path correctly enforces this limit, the receive path (`process_frame()`) fails to validate incoming control frame lengths. When an oversized PING is received, the library attempts to echo it back; the send path then detects the violation and triggers `protocol_error_and_close()` on itself. This allows a remote, unauthenticated attacker to cause a connection crash or application-level denial of service with a single non-compliant frame.
Affected products
- Red Hat libsoup3 Red Hat Enterprise Linux 10
- Red Hat libsoup Red Hat Enterprise Linux 8, 9
- GNOME libsoup 3.4.4, likely all versions with WebSocket support
Timeline
- 2026-07-14: disclosed: Publicly reported via GNOME GitLab and Red Hat Bugzilla
- 2026-07-14: advisory: NVD published the CVE record