Kubernetes: Handshake messages, such as KeyUpdate, are always considered as state-advancing, regardless of whether a
Affects kubernetesSource GCVE Database
Not known to be exploited · CVSS 7.5 High : upgrade to 1.34.13-r2 soon.
Data as of 11 Nov 2026, 03:50 UTC
- Patch
- Available – fixed in 1.34.13-r2, 4.1.6-r1
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:HExploitation evidence
Disclosed: evidence found.
CVE published 13 Aug 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 10 Nov 2026.
What to do
Upgrade kubernetes to 1.34.13-r2; argo-workflows to 4.1.6-r1.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
CleanStartkubernetespkg:apk/cleanstart/kubernetesOther threats | Affected
| Fixed in
|
CleanStartargo-workflowspkg:apk/cleanstart/argo-workflowsOther threats | Affected
| Fixed in
|
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
AI-suggested
A patch is available and has been released in Kubernetes versions 1.34.13-r2 and 4.1.6-r1. Users should upgrade to these fixed versions or later to remediate the vulnerability. No other mitigation or workaround is indicated.
Description
CVE-2026-56862 is a high-severity vulnerability in Kubernetes where handshake messages like KeyUpdate are always treated as state-advancing, even if the handshake has not completed. This behavior affects multiple Kubernetes package versions prior to 1.34.13-r2 and 4.1.6-r1. The flaw can cause denial of service by disrupting the expected handshake state management.