{"answers":{"affected":"It affects 1 product.","exploited":"There is no known exploitation of CVE-2026-18203 in the wild and no public exploit code.","fix":"No fix has been published for CVE-2026-18203 yet. Limit exposure of the affected software until one is available.","what":"CVE-2026-18203 is a medium-severity authentication bypass vulnerability in Redhat Build of Keycloak, published on 31 Jul 2026. Any signed-in user can exploit it over the network, with no action from the victim."},"fix_prompt":"Check this codebase for CVE-2026-18203 and fix it if it is affected.\n\nWhat it is: CVE-2026-18203 is a medium-severity authentication bypass vulnerability in Redhat Build of Keycloak, published on 31 Jul 2026. Any signed-in user can exploit it over the network, with no action from the victim.\nExploitation: There is no known exploitation of CVE-2026-18203 in the wild and no public exploit code.\n\nAffected product: Redhat Build of Keycloak. No package-level version data is available, so check the vendor advisory linked from the reference page.\n\nTask:\n1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.\n2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.\n3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.\n4. Run the tests and summarise what changed and why.\n5. If nothing in the project is affected, say so and change nothing.\n\nReference: https://insights.sbomify.com/CVE-2026-18203/ (Markdown: https://insights.sbomify.com/CVE-2026-18203/index.md)","id":"CVE-2026-18203","markdown":"https://insights.sbomify.com/CVE-2026-18203/index.md","name":"CVE-2026-18203","record":{"aliases":["GHSA-wx5m-whr8-48h5"],"analysis":{"component_type":"server_software","fix_type":"patch","impacts":["privilege_escalation","security_bypass"],"network_reachable":"yes","non_default_config":true,"product_category":"Identity and Access Management","requires_auth":"low_privilege","summary":"Attackers can bypass group-based access controls by exploiting a flawed prefix check, gaining unauthorized access to administrative functions.","user_interaction":"not_required","vuln_class":"auth_bypass"},"analysis_generated_by":"qwen3.8-flash-next","assigner":"redhat","cpe":[{"product":"build_of_keycloak","vendor":"redhat"}],"cvss":{"score":6.5,"severity":"medium","source":"cna","vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N","version":"3.1"},"cwes":[{"id":"CWE-863","name":"Incorrect Authorization"}],"description":"A flaw was found in the group policy evaluation logic of Keycloak, an identity and access management solution. When a group policy is set to extend permissions to child groups, the system incorrectly uses a simple text-based prefix check to verify group membership. This allows a user who belongs to a different group with a similar starting name to bypass security checks and gain unauthorized access to administrative functions or protected resources.","ecosystems":[],"exploits":{"exploitdb":0,"first_seen":null,"github_poc":0,"max_poc_stars":null,"metasploit":0,"nuclei":0,"refs":[],"tier":"none_known"},"has_fix":null,"headline":"Keycloak-services: keycloak-services: group policy extendchildren matches sibling group path prefixes","id":"CVE-2026-18203","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":null,"product":"redhat:build_of_keycloak","products":["redhat:build_of_keycloak"],"type":"auth_bypass","year":"2026"},"n_packages":0,"n_references":2,"next":{"headline":"XSS in Ticimax Informatics' Ticimax E-Commerce Platform","id":"CVE-2026-18205"},"packages":[],"prev":{"headline":"JetEngine \u003c 3.8.14 - Author+ Stored XSS via SVG Upload","id":"CVE-2026-18202"},"products":["Red Hat Build of Keycloak","Red Hat Data Grid 8","Red Hat JBoss Enterprise Application Platform Expansion Pack","Red Hat Single Sign-On 7"],"published":"2026-07-31","related":[{"cvss_score":8.8,"headline":"Keycloak-services: keycloak-services: dcr protocol mapper type-swap policy bypass allows privilege escalation","id":"CVE-2026-15572","kev_date_added":null,"published":"2026-08-05"},{"cvss_score":8.8,"headline":"Keycloak SAML Broken has Authentication Bypass by Primary Weakness","id":"CVE-2026-3047","kev_date_added":null,"published":"2026-03-05"},{"cvss_score":8.1,"headline":"Keycloak-services: keycloak-services: authorization bypass via unnormalized uri matching in pathmatcher","id":"CVE-2026-15573","kev_date_added":null,"published":"2026-08-05"},{"cvss_score":8.1,"headline":"Keycloak-services: keycloak-services: default dcr policy allows role forgery via user property mappers","id":"CVE-2026-16102","kev_date_added":null,"published":"2026-08-05"},{"cvss_score":8.1,"headline":"Org.keycloak/keycloak-quarkus-server: keycloak: unauthorized access via jwt authorization grant with disabled users","id":"CVE-2026-1609","kev_date_added":null,"published":"2026-07-16"},{"cvss_score":8.1,"headline":"Org.keycloak:keycloak-services: keycloak: authentication bypass via jwt algorithm confusion","id":"CVE-2026-11800","kev_date_added":null,"published":"2026-06-25"},{"cvss_score":8.1,"headline":"Keycloak-policy-enforcer: keycloak policy enforcer: authorization bypass via incorrect uri comparison","id":"CVE-2026-9800","kev_date_added":null,"published":"2026-06-25"}],"sources":[{"class":"attribution","licence":"CVE Terms of Use (MITRE)","name":"CVE List","prefix":"CVE"},{"class":"attribution","licence":"US public information, NVD API terms","name":"NVD"},{"class":"attribution","licence":"CWE Terms of Use","name":"CWE (MITRE)"},{"class":"attribution","licence":"FIRST CVSS licence","name":"CVSS (FIRST)"}],"ssvc":{"automatable":"no","exploitation":"none","technical_impact":"partial"},"state":"PUBLISHED","updated":"2026-08-31","vendors":["Red Hat"]},"summary":"Attackers can bypass group-based access controls by exploiting a flawed prefix check, gaining unauthorized access to administrative functions.","url":"https://insights.sbomify.com/CVE-2026-18203/"}