PT-2026-29882 · Xml2Js+2 · Xml2Js+2

Dmbs335 · Published 2026-04-02 · Updated 2026-04-14 · CVE-2026-34840

Positive Technologies (AI Summary)

CVSS v3.1

8.1

High

Base vector

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

Name of the Vulnerable Software and Affected Versions OneUptime versions prior to 10.0.42

Description OneUptime, an open-source monitoring and observability platform, had a flaw in its SAML SSO implementation located in App/FeatureSet/Identity/Utils/SSO.ts. The issue stemmed from a separation between signature verification and identity extraction. The isSignatureValid() function verified the signature of the first element using xml-crypto, while the getEmail() function always retrieved the email from the first assertion via xml2js. This allowed an attacker to prepend an unsigned assertion containing an arbitrary identity before a legitimately signed assertion, leading to authentication bypass.

Recommendations Update to version 10.0.42 or later.

Fix

Improper Verification of Cryptographic Signature

Weakness Enumeration

CWE-347

Related Identifiers

CVE-2026-34840

Affected Products

Oneuptime

Xml-Crypto

Xml2Js

References · 7

• https://github.com/OneUptime/oneuptime/security/advisories/GHSA-5w5c-766x-265g · Vendor Advisory
• https://github.com/OneUptime/oneuptime/commit/2fd7ede52f60444710628d6c1b34dee2ef9e57d1 · Patch
• https://nvd.nist.gov/vuln/detail/CVE-2026-34840 · Security Note
• https://github.com/OneUptime/oneuptime/releases/tag/10.0.42 · Note
• https://twitter.com/TheHackerWire/status/2039900990103773693 · Twitter Post
• https://twitter.com/CVEnew/status/2040128779108970631 · Twitter Post
• https://twitter.com/giuseppe_1337/status/2043851103498895864 · Twitter Post