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Vulnerability record · CVE-2026-15556 · published 11 August 2026

CVE-2026-15556: Improper verification of cryptographic signature vulnerability

A flaw was found in Picketlink's SP signature validation; a SAML response containing zero assertion elements matching the signature check can allow an attacker to forge a SAML response and auth as any principal with any roles on the protected application.

8.1 CVSS 3.1 High EPSS 0.24% · top 86.6% CWE-347 · Improper verification of cryptographic signature Awaiting Analysis
8.1CVSS 3.1 base score
0.24%EPSS exploitation probability, 30 days
NoNot in CISA KEV
0Affected product versions listed by NVD
6References
25 Sep 2026Last modified by NVD

Description

A flaw was found in Picketlink's SP signature validation; a SAML response containing zero assertion elements matching the signature check can allow an attacker to forge a SAML response and auth as any principal with any roles on the protected application.

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N

References

LinkTags
https://access.redhat.com/errata/RHSA-2026:53644
https://access.redhat.com/errata/RHSA-2026:53645
https://access.redhat.com/errata/RHSA-2026:53646
https://access.redhat.com/errata/RHSA-2026:53806
https://access.redhat.com/security/cve/CVE-2026-15556
https://bugzilla.redhat.com/show_bug.cgi?id=2483121

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Same products first, then exploited flaws of the same weakness class.

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Source: NIST National Vulnerability Database (record CVE-2026-15556), CISA KEV, FIRST EPSS (scores of 2026-09-26). This page is refreshed as NVD updates the record.