CVE-2026-18212 (GCVE-0-2026-18212)
Vulnerability from cvelistv5
Published
2026-09-16 14:54
Modified
2026-09-16 18:35
Severity ?
VLAI Severity ?
EPSS score ?
CWE
- CWE-401 - Missing Release of Memory after Effective Lifetime
Summary
A flaw was found in the SAML Redirect Binding implementation of Keycloak, an open-source identity and access management solution. The issue occurs because the custom DEFLATE compression and decompression helpers fail to release native zlib memory after use. An unauthenticated attacker can exploit this by sending repeated malformed SAML requests, leading to native memory exhaustion and a denial of service.
References
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Impacted products
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| Red Hat | Red Hat build of Keycloak 26.4 |
Unaffected: 26.4.16-2 < * cpe:/a:redhat:build_keycloak:26.4::el9 |
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Sightings
| Author | Source | Type | Date |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or seen somewhere by the user.
- Confirmed: The vulnerability is confirmed from an analyst perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: This vulnerability was exploited and seen by the user reporting the sighting.
- Patched: This vulnerability was successfully patched by the user reporting the sighting.
- Not exploited: This vulnerability was not exploited or seen by the user reporting the sighting.
- Not confirmed: The user expresses doubt about the veracity of the vulnerability.
- Not patched: This vulnerability was not successfully patched by the user reporting the sighting.
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