Quick answers
- Is CVE-2026-104034 exploited in the wild?
- No. Junglewise Threat Intelligence has no report of CVE-2026-104034 being exploited in the wild.
- How severe is CVE-2026-104034?
- Medium severity, with a CVSS score of 4.7, published 6 October 2026.
- Which products and versions are affected?
- Red Hat SSSD.
- Is there a fix for CVE-2026-104034?
- No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.
- How is CVE-2026-104034 attacked?
- It is attacked with local access, in a hosted service.
- Am I affected by CVE-2026-104034?
- Check whether you run Red Hat SSSD. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.
Technical details
A use-after-free vulnerability exists in the KCM responder during Kerberos TGT renewal, where a deferred callback accesses memory that has already been freed. Exploitation requires local authenticated access with a renewable Kerberos ticket and relies on the non-default KCM renewal feature being configured. Successful exploitation crashes the KCM responder service, resulting in a localized denial of service without credential exposure or privilege escalation.
Affected products
- Red Hat SSSD
Timeline
- 2026-10-06: disclosed