Cockpit: cockpit: denial of service via unbounded connection thread spawning
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- None
- Attack complexity
- Low
- Impact type
- Denial of service
- Confidentiality · integrity · availability
- None · None · High
- Fix status
- Partial Red Hat: 2 fixed, 3 without a fix
Attack profile from CVSS 3.1 · CNA. Fix status from CNA and Red Hat. Impact type from CWE-770.
Summary
A flaw was found in Cockpit. An unauthenticated remote attacker can exploit this vulnerability by initiating and sustaining numerous simultaneous connections to the `cockpit-tls` service. This forces the service to create an unbounded number of detached threads, consuming system resources such as memory and file descriptors. The primary consequence is a denial of service (DoS), leading to degradation or complete unavailability of the Cockpit service for legitimate users.
Why it matters now
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- Yes
- Technical impact
- Partial
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| Red Hat | Red Hat Enterprise Linux 9 | — | 356.4-1.el9_8 | Patch available | CNA |
| Red Hat | Red Hat Enterprise Linux 9 | — | 356.4-1.el9_8 | Patch available | CNA |
| Red Hat | Red Hat Enterprise Linux 10 | — | — | No fix listed | CNA |
| Red Hat | Red Hat Enterprise Linux 7 | — | — | No fix listed | CNA |
| Red Hat | Red Hat Enterprise Linux 8 | — | — | No fix listed | CNA |
| Red Hat | Red Hat OpenShift Dev Spaces | — | — | Not affected | CNA |
| Red Hat | Red Hat OpenShift Dev Spaces | — | — | Not affected | CNA |
| Red Hat | Red Hat OpenShift Dev Spaces | — | — | Not affected | CNA |
- Red Hat Enterprise Linux 9 VendorRed Hat Affected — Fixed in 356.4-1.el9_8 Patch available CNA
- Red Hat Enterprise Linux 9 VendorRed Hat Affected — Fixed in 356.4-1.el9_8 Patch available CNA
- Red Hat Enterprise Linux 10 VendorRed Hat Affected — Fixed in — No fix listed CNA
- Red Hat Enterprise Linux 7 VendorRed Hat Affected — Fixed in — No fix listed CNA
- Red Hat Enterprise Linux 8 VendorRed Hat Affected — Fixed in — No fix listed CNA
- Red Hat OpenShift Dev Spaces VendorRed Hat Affected — Fixed in — Not affected CNA
- Red Hat OpenShift Dev Spaces VendorRed Hat Affected — Fixed in — Not affected CNA
- Red Hat OpenShift Dev Spaces VendorRed Hat Affected — Fixed in — Not affected CNA
CPE names CNA · 6
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:/a:redhat:enterprise_linux:9::appstream | 9 | — | Red Hat |
| cpe:/o:redhat:enterprise_linux:9::baseos | 9 | — | Red Hat |
| cpe:/a:redhat:enterprise_linux:10 | 10 | — | Red Hat |
| cpe:/o:redhat:rhel_els:7 | 7 | — | Red Hat |
| cpe:/a:redhat:enterprise_linux:8 | 8 | — | Red Hat |
| cpe:/a:redhat:openshift_devspaces:3 | 3 | — | Red Hat |
- cpe:/a:redhat:enterprise_linux:9::appstream Versions 9 — ·Red Hat
- cpe:/o:redhat:enterprise_linux:9::baseos Versions 9 — ·Red Hat
- cpe:/a:redhat:enterprise_linux:10 Versions 10 — ·Red Hat
- cpe:/o:redhat:rhel_els:7 Versions 7 — ·Red Hat
- cpe:/a:redhat:enterprise_linux:8 Versions 8 — ·Red Hat
- cpe:/a:redhat:openshift_devspaces:3 Versions 3 — ·Red Hat
Remediation
Red Hat 1 advisory
- RHSA-2026:94533 Released 2026-11-03 · Red Hat rating Importantcockpit security update
- Red Hat Enterprise Linux AppStream (v. 9) cockpit-packagekit-356.4-1.el9_8, cockpit-storaged-356.4-1.el9_8
- Red Hat Enterprise Linux BaseOS (v. 9) cockpit-356.4-1.el9_8, cockpit-bridge-356.4-1.el9_8, cockpit-doc-356.4-1.el9_8 +3
Vendor assessments
Red Hat
Red Hat rating: Important. Red Hat's page for this CVE →
| Product | Status | Plan or fix |
|---|---|---|
| Red Hat Enterprise Linux 10 | Affected | No fix yet |
| Red Hat Enterprise Linux 7 | Affected | No fix yet |
| Red Hat Enterprise Linux 8 | Affected | No fix yet |
| Red Hat Enterprise Linux AppStream (v. 9) | Fixed | RHSA-2026:94533 |
| Red Hat Enterprise Linux BaseOS (v. 9) | Fixed | RHSA-2026:94533 |
Not affected: 1 product
- Red Hat OpenShift Dev Spaces
Timeline
- 2026-10-02 Threatist record created from CVE-2026-91149
- 2026-10-03 Alias added: GHSA-3m8q-36jp-wgm3
- 2026-10-04 Priority changed: MEDIUM → LOW
- 2026-11-03 Fix available: cockpit@0:356.4-1.el9_8 · CNA
- 2026-11-03 1 new reference · CNA
- 2026-11-04 Fix available: RHSA-2026:94533 · Red Hat
- 2026-11-04 Fix available: Red Hat Enterprise Linux AppStream (v. 9), Red Hat Enterprise Linux BaseOS (v. 9) · Red Hat
- 2026-11-06 Priority changed: LOW → MEDIUM
References
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Sources
- CVE-2026-91149 · CVE Program
- CVE-2026-91149 · NVD
- FIRST EPSS
- GHSA-3m8q-36jp-wgm3 · GitHub Advisory Database · CC BY 4.0
- CVE-2026-91149 · Red Hat security data · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences