CVE-2026-34840

Description

OneUptime is an open-source monitoring and observability platform. Prior to version 10.0.42, OneUptime's SAML SSO implementation (App/FeatureSet/Identity/Utils/SSO.ts) has decoupled signature verification and identity extraction. isSignatureValid() verifies the first <Signature> element in the XML DOM using xml-crypto, while getEmail() always reads from assertion[0] via xml2js. An attacker can prepend an unsigned assertion containing an arbitrary identity before a legitimately signed assertion, resulting in authentication bypass. This issue has been patched in version 10.0.42.

Weakness classification

• CWE-347: Improper Verification of Cryptographic Signature

Primary references

• security-advisories@github.com — Patch
• security-advisories@github.com — Product, Release Notes
• security-advisories@github.com — Exploit, Mitigation, Vendor Advisory