Public vulnerability disclosure

CVE-2026-91150

Cockpit: cockpit: denial of service via unbounded fragmented websocket messages

publishedCWE-770

A flaw was found in Cockpit. This vulnerability allows a remote attacker, without prior authentication, to send specially crafted fragmented WebSocket messages. These messages accumulate without a total-size limit, leading to unbounded memory exhaustion and a denial of service in the `cockpit-ws` service.

Technical severity7.5 highCVSS 3.1 · CNA: redhat
Published2026-11-11Source updated 2026-11-11
Collected2026-11-111 attributed source

Fixes and workarounds

No remediation reported in collected sources.

Missing remediation information is not evidence that no patch exists.

Affected products and versions

Affected products, source version ranges and reporting authorities
ProductVersionsAuthority
Red Hat Enterprise Linux 10
Red Hat
cockpit
https://access.redhat.com/downloads/content/package-browser/
Range not reported
Other versions: affected
CNA: redhat
Red Hat Enterprise Linux 7
Red Hat
cockpit
https://access.redhat.com/downloads/content/package-browser/
Range not reported
Other versions: affected
CNA: redhat
Red Hat Enterprise Linux 8
Red Hat
cockpit
https://access.redhat.com/downloads/content/package-browser/
Range not reported
Other versions: affected
CNA: redhat
Red Hat Enterprise Linux 9
Red Hat
cockpit
https://access.redhat.com/downloads/content/package-browser/
Range not reported
Other versions: affected
CNA: redhat
Red Hat OpenShift Dev Spaces
Red Hat
devspaces/udi-base-rhel10
https://access.redhat.com/downloads/content/package-browser/
Range not reported
Other versions: affected
CNA: redhat
Red Hat OpenShift Dev Spaces
Red Hat
devspaces/udi-base-rhel9
https://access.redhat.com/downloads/content/package-browser/
Range not reported
Other versions: affected
CNA: redhat
Red Hat OpenShift Dev Spaces
Red Hat
devspaces/udi-rhel9
https://access.redhat.com/downloads/content/package-browser/
Range not reported
Other versions: affected
CNA: redhat

Version ranges are source assertions. Check the vendor advisory and your installed configuration before determining exposure.

CVSS assessments

CVSS scores, vectors and reporting authorities
Version / scoreVectorAuthority
3.1 / 7.5
high
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:HCNA: redhat

Exploit evidence

No exploit evidence in collected sources. This is not proof of no exploitation.

References

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