CVE-2026-34840

8.1 HIGH
Published: April 02, 2026 Modified: April 13, 2026
View on NVD

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.

AI Explanation

Get an AI-powered plain-language explanation of this vulnerability and remediation steps.

Login to generate AI explanation

CVSS v3.x Details

0.0 Low Medium High Critical 10.0
Vector String
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N

References to Advisories, Solutions, and Tools

Patch Vendor Advisory Exploit Third Party Advisory
https://github.com/OneUptime/oneuptime/releases/tag/10.0.42
Source: security-advisories@github.com
Product Release Notes
https://github.com/OneUptime/oneuptime/security/advisories/GHSA-5w5c-766x-265g
Source: security-advisories@github.com
Exploit Mitigation Vendor Advisory

3 reference(s) from NVD

Quick Stats

CVSS v3 Score
8.1 / 10.0
EPSS (Exploit Probability)
0.1%
19th percentile
Exploitation Status
Not in CISA KEV

Weaknesses (CWE)

Affected Vendors

hackerbay