CVE-2026-34840

HIGH EPSS 17.7%
Published Apr 2, 20262mo ago · Modified Jun 17, 20261w ago
8.1 CVSS 3.1
High
Find Similar
Published Apr 2, 2026 2mo ago
Last Modified Jun 17, 2026 1w ago

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.

CVSS Details

Base Score
8.1
Exploitability
2.8
Impact
5.2
Vector string
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N
Attack Vector Network
Attack Complexity Low
Privileges Required Low
User Interaction None
Scope Unchanged
Confidentiality High
Integrity High
Availability None

Threat Intelligence

EPSS Exploit Probability
17.7% percentile
Exploit & Patch Status
Public Exploit Known
Patch Available

Weaknesses 1

CWE-347

Affected Products 1

VendorProductVersionRange
hackerbayoneuptime* <10.0.42

References 3

  • github.com https://github.com/OneUptime/oneuptime/commit/2fd7ede52f60444710628d6c1b34dee2ef9e57d1
    Patch
  • github.com https://github.com/OneUptime/oneuptime/releases/tag/10.0.42
    ProductRelease Notes
  • github.com https://github.com/OneUptime/oneuptime/security/advisories/GHSA-5w5c-766x-265g
    ExploitMitigationVendor Advisory

Remediation

  • github.com https://github.com/OneUptime/oneuptime/commit/2fd7ede52f60444710628d6c1b34dee2ef9e57d1
    Patch