PatchTheCVECVE-2026-55996: A denial-of-service vulnerability was identified in multiple TLS listeners in Rancher
19
Routine
MEDIUM 4.3
CVE-2026-55996 is a medium-severity flaw (CVSS 4.3) affecting affected software. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.
A denial-of-service vulnerability was identified in multiple TLS listeners in Rancher. Both the cattle-cluster-agent component running in downstream clusters and the Rancher server itself use the dynamiclistener library to serve TLS traffic. Without an effective CN filter configured, dynamiclistener automatically appended to each serving certificate any hostname presented via Server Name Indication (SNI) in incoming TLS requests. An unauthenti
Why this priority
- No elevated risk signals yet
No fix is published yet: follow the downgrade or mitigation steps.
Risk facts
| CVSS score | 4.3 (Medium) |
| Attack vector | Network (remote) |
| Attack complexity | Low |
| Privileges needed | Low |
| User interaction | None |
| EPSS exploit chance | 0.2% (top 85%) |
| CISA exploited list | No |
| Weakness | CWE-770 |
| Published | 2026-08-05 |
| Last modified | 2026-10-23 |
Publisher (CNA): SUSE
Timeline
- Published CVE record published
- Updated Record last modified
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Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.
Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.