CVE-2026-15573: redhat build_of_keycloak
Vulnerability summary
CVE-2026-15573 is a high (CVSS 8.1) vulnerability in redhat build_of_keycloak. EPSS estimates a 0.46% chance of exploitation in the next 30 days, higher than 38.3% of scored vulnerabilities.
Timeline
- 05-08-2026PublishedVulnerability first disclosed.
- 31-08-2026Last modifiedVulnerability information updated.
Description
A flaw was found in Keycloak's Authorization Services. The component responsible for matching request paths to security policies (PathMatcher) does not properly normalize URIs before comparison. By adding extra characters like a trailing slash or matrix parameters to a URL, an attacker can trick the system into applying a less restrictive security policy than intended. This allows an authenticated user to access administrative or restricted areas they should not have permission to see.
CVSS metrics
2 scores · 2 sources · 1 version- NVDNIST8.1HighCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N
EPSS trend
Probability
0.46%
Chance of exploitation in the next 30 days
Percentile
38%
Versus all other CVEs
30-day change
+0.14 pp
From 0.32% on 18-09-2026
Known exploited
Compare KEV catalogsNot in any of the 3 tracked catalogs.
Public exploits
0 foundNo public exploits indexed.
Weaknesses
CWE · root cause- CWE-551Incorrect Behavior Order: Authorization Before Parsing and CanonicalizationIf a web server does not fully parse requested URLs before it examines them for authorization, it may be possible for an attacker to bypass authorization protection.
- CWE-178Improper Handling of Case SensitivityThe product does not properly account for differences in case sensitivity when accessing or determining the properties of a resource, leading to inconsistent results.
Affected systems
Redhat4 products
- build_of_keycloak≥ 26.4, < 26.4.14 | ≥ 26.6, < 26.6.5
- data_grid8.0
- jboss_enterprise_application_platform_expansion_packna
- single_sign-on7.0
1 vendor · 4 products