CVE-2026-18047 Dogtag-pki: pki-core: redhat-pki: pki: acme admin enable/disable endpoint authentication bypass via trailing slash
Unauthenticated attackers can bypass authentication on ACME admin endpoints via trailing slash manipulation, allowing unauthorized service state changes and denial of service.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2026-18047?
CVE-2026-18047 is a medium-severity authentication bypass vulnerability in Red Hat Certificate System 10, published on 28 Jul 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
A flaw was found in Dogtag PKI's ACME responder where the web.xml security constraints use exact URL pattern matching for admin-only enable/disable endpoints. By appending a trailing slash to the URL, an unauthenticated attacker can bypass the Tomcat authentication constraint while RESTEasy still routes the request to the handler, allowing unauthorized toggling of the ACME service state including persistent denial of service.
Weakness: CWE-288
Which versions are affected by CVE-2026-18047?
How do I fix CVE-2026-18047?
No fix has been published for CVE-2026-18047 yet. Limit exposure of the affected software until one is available.
Upgrade, and rotate credentials and sessions that may have been exposed. More about Authentication bypass.
Is CVE-2026-18047 being exploited?
There is no known exploitation of CVE-2026-18047 in the wild and no public exploit code.
Sources
Also known as DEBIAN-CVE-2026-18047, GHSA-5xgg-8pvj-x39g, UBUNTU-CVE-2026-18047.