{"id":"CVE-2026-34840","title":"OneUptime is an open-source monitoring and observability platform","summary":"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. isSigna…","severity":"high","cvss":8.1,"cvssVector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N","cwe":["CWE-347"],"vendor":"hackerbay","product":"oneuptime","affected":["oneuptime < 10.0.42"],"patched":["oneuptime 10.0.42"],"published":"2026-04-02","updated":"2026-10-06","sourceUpdated":"2026-10-06T22:10:00.247","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-34840","references":[{"url":"https://github.com/OneUptime/oneuptime/commit/2fd7ede52f60444710628d6c1b34dee2ef9e57d1","label":"security-advisories@github.com"},{"url":"https://github.com/OneUptime/oneuptime/releases/tag/10.0.42","label":"security-advisories@github.com"},{"url":"https://github.com/OneUptime/oneuptime/security/advisories/GHSA-5w5c-766x-265g","label":"security-advisories@github.com"}],"tags":["nvd"],"epss":0.00343,"epssPercentile":0.25661,"ingestedAt":"2026-10-06T22:23:15.913Z","slug":"CVE-2026-34840","body":"## Overview\n\nOneUptime 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.\n\n## Affected\n\n- `oneuptime < 10.0.42`\n\n## Remediation\n\nUpgrade past the affected range:\n\n- `oneuptime 10.0.42`","depth":"twilight","depthScore":45,"depthScoreParts":{"impact":44.6,"likelihood":0.1,"exploitation":0,"ransomware":0},"changes":[]}