CVE-2026-87802criticalCWE-347

CVE-2026-87802: critical vulnerability in Apache Syncope

Apache Syncope: SRA OAuth2 JWT signature verification bypass

Published

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28Vexday Risk Score

No sign of exploitation. No public exploitation artifact known so far.

ssvc Trackcvss 9.1epss 0.3%
Improper verification of cryptographic signature vulnerability in Apache Syncope. When SRA is configured for OAuth 2.0 without JWKS set URI assigned, an attacker can forge arbitrary JWTs to impersonate any user identity and permissions, gaining full access to services proxied by SRA. This issue affects Apache Syncope: from 3.0.0-M0 through 3.0.16, from 4.0.0-M0 through 4.0.7, from 4.1.0-M0 through 4.1.2. Users are recommended to upgrade to version 4.0.8 / 4.1.3, which fix this issue.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
Affected products
Apache Software Foundation · Apache Syncope
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