CVE-2026-87802 Apache Syncope: SRA OAuth2 JWT signature verification bypass
Attackers can forge JWTs to impersonate users and gain full access to proxied services if SRA OAuth2 is configured without a JWKS URI.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2026-87802?
CVE-2026-87802 is a critical authentication bypass vulnerability in Apache Syncope, published on 14 Sep 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
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.
Weakness: CWE-347
Which versions are affected by CVE-2026-87802?
How do I fix CVE-2026-87802?
No fix has been published for CVE-2026-87802 yet. Limit exposure of the affected software until one is available.
Upgrade, and rotate credentials and sessions that may have been exposed. More about Authentication bypass.
Is CVE-2026-87802 being exploited?
There is no known exploitation of CVE-2026-87802 in the wild and no public exploit code.
Sources
Also known as GHSA-mg52-7466-j5f7.