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CRITICAL

CVE-2026-87802

CVSS v3

9.1

CRITICAL

EPSS Score

0.3 %

exploit probability, as of 2026-09-28

CISA KEV

No

known exploited

Exploitation

—

SSVC status

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.

Technical details

Published
2026-09-14
Last Modified
2026-09-14

Frequently asked questions

What is CVE-2026-87802?

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.

Is CVE-2026-87802 actively exploited?

Active exploitation of CVE-2026-87802 has not been confirmed. Its EPSS score was 0.3% on 2026-09-28, the estimated probability of exploitation in the next 30 days.

What is the CVSS score for CVE-2026-87802?

CVE-2026-87802 has a CVSS v3 base score of 9.1 (CRITICAL severity).

Is CVE-2026-87802 affecting your environment?

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