What’s Vulnerable › Vulnerabilities

CVE-2026-89058: Resteasy-core: resteasy: corsfilter reflects arbitrary origin with credentials under wildcard config

• Severity: high (CVSS 7.4 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 0.3% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2026-09-18 · updated 2026-10-29
• Weakness: CWE-346

Description

A flaw was found in RESTEasy's CorsFilter, which, when configured to allow all origins ("*"), reflects the request's Origin header back in the Access-Control-Allow-Origin response together with Access-Control-Allow-Credentials: true. This permissive cross-origin policy allows a malicious website to make credentialed cross-origin requests and read authenticated responses from a victim's session, resulting in a loss of confidentiality.

Affected products

• Red Hat build of Keycloak 26.4: all versions
• Red Hat build of Apache Camel 4 for Quarkus 3: all versions
• Red Hat build of Apicurio Registry 3: all versions
• Red Hat build of Debezium 3: all versions
• Red Hat build of Quarkus 3.27.6.redhat: all versions — fixed in 6.2.19.Final-redhat-00003
• Red Hat build of Quarkus 3.33.4.redhat: all versions — fixed in 6.2.19.Final-redhat-00003
• Red Hat Certificate System 10: all versions
• Red Hat Certificate System 11: all versions
• Red Hat Enterprise Linux 10: all versions — fixed in 0:11.9.0-6.el10_2.1
• Red Hat Enterprise Linux 9: all versions — fixed in 0:3.0.26-20.el9_8.1
• Red Hat Fuse 7: all versions
• Red Hat JBoss Enterprise Application Platform 7: all versions
• Red Hat JBoss Enterprise Application Platform 8: all versions
• Red Hat JBoss Enterprise Application Platform Expansion Pack: all versions
• Red Hat Single Sign-On 7: all versions
• Red Hat, Inc. resteasy: before 6.2.19.Final; from 7.0.0.Alpha1 before 7.0.5.Final — fixed in 6.2.19.Final, 7.0.5.Final

How to fix

Upgrade to a fixed version: Red Hat build of Quarkus 3.27.6.redhat 6.2.19.Final-redhat-00003; Red Hat build of Quarkus 3.33.4.redhat 6.2.19.Final-redhat-00003; Red Hat Enterprise Linux 10 0:11.9.0-6.el10_2.1; Red Hat Enterprise Linux 9 0:3.0.26-20.el9_8.1; Red Hat, Inc. resteasy 6.2.19.Final, 7.0.5.Final. Check the vendor advisory for mitigations.

References

• https://access.redhat.com/errata/RHSA-2026:83082
• https://access.redhat.com/errata/RHSA-2026:83520
• https://access.redhat.com/errata/RHSA-2026:85234
• https://access.redhat.com/errata/RHSA-2026:92408
• https://access.redhat.com/security/cve/CVE-2026-89058
• https://bugzilla.redhat.com/show_bug.cgi?id=2519775
• https://github.com/resteasy/resteasy/commit/efeb2b7
• https://github.com/resteasy/resteasy/security/advisories/GHSA-972r-f3fv-whm3
• https://github.com/resteasy/resteasy/security/advisories/GHSA-972r-f3fv-whm3

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