CVE-2026-15711
What it is
A vulnerability was found in libsoup's WebSocket frame parsing implementation. The library fails to validate length rules specified in RFC 6455 §5.5, which mandates that all WebSocket control frames (e.g., PING, PONG, CLOSE) contain a payload of 125 bytes or less. A remote, unauthenticated attacker can exploit this by sending a non-compliant, oversized control frame. Because the parser handles this protocol violation improperly instead of throwing an immediate connection termination error, it triggers a internal processing crash, resulting in a remote denial of service (DoS) for applications utilizing libsoup WebSockets.
At a glance
- Exploitability
- Can be exploited over the network without logging in. High risk of service disruption.
- Exploit odds
- 0.7% chance of exploitation in the next 30 days (EPSS).
- Fix
- No patch or advisory is linked yet. Look at mitigations or restrict exposure.
Timeline
- PublishedDisclosed publicly on CVE.org and NVD
- Last updatedMost recent change to the record
Why it ranks here
- Exploited in the wild: no, CISA does not list it.
- Exploit odds: 0.7% in the next 30 days (EPSS).
- Severity: 7.5 HIGH (CVSS).
- Fix: none linked yet, which raises it.
Details
- Published
- Last modified
- Exploit probability
- 0.7% · EPSS, next 30 days
- Weakness
- CWE-770 · Allocation without limits
- Record status
- Deferred
Attack profile CVSS 3.1 · 7.5
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- None
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- None
- Integrity
- None
- Availability
- High
Raw vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Is it in your code?
Hand this to your coding agent. It searches your project for the affected products and checks versions. Nothing leaves your machine.
Read https://cve-list.com/agent/cve/CVE-2026-15711.md and follow it. Check whether this project is affected by CVE-2026-15711. Read only. Don't change anything and don't upload my code. Tell me yes, no or not sure, with the file as proof.
References
- https://access.redhat.com/errata/RHSA-2026:68234
- https://access.redhat.com/errata/RHSA-2026:68235
- https://access.redhat.com/errata/RHSA-2026:68266
- https://access.redhat.com/errata/RHSA-2026:68612
- https://access.redhat.com/errata/RHSA-2026:69108
- https://access.redhat.com/errata/RHSA-2026:69297
- https://access.redhat.com/errata/RHSA-2026:69863
- https://access.redhat.com/errata/RHSA-2026:70598
- https://access.redhat.com/errata/RHSA-2026:70599
- https://access.redhat.com/errata/RHSA-2026:71389
- https://access.redhat.com/security/cve/CVE-2026-15711
- https://bugzilla.redhat.com/show_bug.cgi?id=2499924
- https://gitlab.gnome.org/GNOME/libsoup/-/issues/515
- https://gitlab.gnome.org/GNOME/libsoup/-/issues/515