Keycloak-services: keycloak-services: unauthenticated jvm termination via saml 1.1 authoritybinding parsing loop
Affects Red Hat Build of Keycloak and Red Hat Single Sign-On 7 when a SAML 1.1 assertion's AuthenticationStatement contains an AuthorityBinding child element. No vendor rating or fix is listed in the facts.
Written by anthropic/claude-haiku-5.5 from the sources below. Verify against them.
- Exploited
- No known exploitation
- Fix
- No fix listed
- Who is exposed
- Not reported
Do first: Workaround: The facts contain no workaround or interim mitigation from the vendor. No official step to take while a fix is unavailable is stated.
- Last modified
- A 0-100 score for how much a CVE matters across the industry: exploitation, exposure, how widely the software is used, severity and whether a fix exists.What do these mean? →
- 40/100 · provisional
- How many real-world setups can hit the bug, from the vendor's advisory and CISA data. It does not know your setup.What do these mean? →
- Unclear
- Whether working attack code is public (Exploit-DB, Metasploit, Nuclei or GitHub). Public code makes attacks easier.What do these mean? →
- None on Exploit-DB, Metasploit or GitHub
Summary
The Keycloak identity and access management software contains a flaw in its SAML 1.1 assertion parser that an attacker can trigger remotely, without logging in, by sending a crafted AuthorityBinding element. The bug can make the service consume all available memory and crash, leaving it unavailable to users.
Read the original description
A flaw was found in the SAML 1.1 assertion parser of Keycloak, a tool used for identity and access management. The issue occurs when the parser handles a specific element called AuthorityBinding within an authentication statement. Due to an incomplete fix for a previous vulnerability, the parser can enter an infinite loop that consumes all available memory, causing the entire Keycloak service to crash and become unavailable to users.
cve.now Index
- Exploitation?/40Unknown. No CISA SSVC exploitation rating yet
- Exposure17/25No login or user action needed, reachable over the network without a login · Unknown: Advisories don't say whether default setups are affected
- Reach10/20Shipped in major Linux distributions
- Severity7.5/10CVSS 7.5
- No patch5/5No patch listed yet
What would change the score
- Would score about 85 if added to CISA KEV
- Would score about 80 if CISA's SSVC rates exploitation active
- Would score about 45 if advisories confirm default setups are exposed
What to do
Workaround: The facts contain no workaround or interim mitigation from the vendor. No official step to take while a fix is unavailable is stated.
Timeline
- CVE published
- First seen by cve.now
Affected versions
- keycloak-services
Version range not reported
- rhbk/keycloak-rhel9
Version range not reported
- keycloak-services
Version range not reported
Evidence 2
- Report
- Link
Corrections
None so far.
Something wrong on this page? Report an error. Every fix is listed here.
Questions about CVE-2026-110931
Is CVE-2026-110931 being exploited?
It is not in CISA's Known Exploited Vulnerabilities catalog, and CISA's SSVC assessment does not mark exploitation as active. That does not mean it has not been attacked: vendors and researchers can report attacks before CISA lists them. No public exploit code is tracked.Source: cve.now feed data
What does this mean?
A parsing flaw in Keycloak's SAML 1.1 handling causes an infinite loop when an AuthenticationStatement includes an AuthorityBinding child element. The loop exhausts memory and terminates the Keycloak JVM, causing a complete denial of service.Source: bugzilla.redhat.com, access.redhat.com
Am I affected, and how do I check?
The listed products are Red Hat Build of Keycloak and Red Hat Single Sign-On 7, but the facts give no version ranges. The trigger is a SAML 1.1 assertion whose AuthenticationStatement contains an AuthorityBinding element, so check the installed product version against Red Hat's advisory and whether SAML 1.1 assertions are processed in the deployment.Source: bugzilla.redhat.com, access.redhat.com
How do I fix CVE-2026-110931?
The facts name no fixed release, so check Red Hat's advisory for the patched version of the affected product line. Confirm the installed version against that advisory.Source: bugzilla.redhat.com, access.redhat.com
What if there's no patch?
The facts contain no workaround or interim mitigation from the vendor. No official step to take while a fix is unavailable is stated.Source: bugzilla.redhat.com, access.redhat.com