{"cve":"CVE-2026-34840","nvd":{"published":"2026-04-02T20:16:28.357","modified":"2026-10-06T22:10:00.247","status":"Analyzed","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_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N","score":8.1},"cwes":["CWE-347"],"references":["https://github.com/OneUptime/oneuptime/commit/2fd7ede52f60444710628d6c1b34dee2ef9e57d1","https://github.com/OneUptime/oneuptime/releases/tag/10.0.42","https://github.com/OneUptime/oneuptime/security/advisories/GHSA-5w5c-766x-265g"],"products":["hackerbay:oneuptime"],"source":"nvd","synced_at":"2026-10-19T22:28:59.047572785+00:00"},"epss":{"cve":"CVE-2026-34840","score":0.00264,"percentile":0.18159,"date":"2026-10-25"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}