CVE-2026-34840
Last modified
CVE-2026-34840 is a high-severity vulnerability rated 8.1/10 on the CVSS scale. 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. EPSS estimates a 0.26% chance of exploitation in the next 30 days.
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.
Metrics
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N
Weakness Enumeration
Affected Software
| Vendor | Product | Versions |
|---|---|---|
| Hackerbay | Oneuptime | < 10.0.42 |
References
- https://github.com/OneUptime/oneuptime/releases/tag/10.0.42Product, Release Notes
- https://github.com/OneUptime/oneuptime/security/advisories/GHSA-5w5c-766x-265gExploit, Mitigation, Vendor Advisory
Timeline
- Published
- Last Modified
- Status
- Analyzed
Frequently Asked Questions
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