{"cve":"CVE-2026-28787","nvd":{"published":"2026-03-06T05:16:39.980","modified":"2026-06-17T10:29:02.663","status":"Analyzed","description":"OneUptime is a solution for monitoring and managing online services. In version 10.0.11 and prior, the WebAuthn authentication implementation does not store the challenge on the server side. Instead, the challenge is returned to the client and accepted back from the client request body during verification. This violates the WebAuthn specification (W3C Web Authentication Level 2, §13.4.3) and allows an attacker who has obtained a valid WebAuthn assertion (e.g., via XSS, MitM, or log exposure) to replay it indefinitely, completely bypassing the second-factor authentication. No known patches are available.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:H","score":9.0},"cwes":["CWE-287","CWE-294"],"references":["https://github.com/OneUptime/oneuptime/security/advisories/GHSA-gjjc-pcwp-c74m"],"products":["hackerbay:oneuptime"],"source":"nvd","synced_at":"2026-10-19T22:25:53.701907451+00:00"},"epss":{"cve":"CVE-2026-28787","score":0.00287,"percentile":0.2128,"date":"2026-10-31"},"kev":null,"osv":[{"id":"GHSA-gjjc-pcwp-c74m","url":"https://osv.dev/vulnerability/GHSA-gjjc-pcwp-c74m","summary":"OneUptime has WebAuthn 2FA bypass: server accepts client-supplied challenge instead of server-stored value, allowing credential replay","modified":"2026-03-06T15:31:30.007205Z","packages":[{"ecosystem":"npm","name":"@oneuptime/common","purl":"pkg:npm/%40oneuptime/common","ranges":["<=10.0.11"],"fixed":[]}]}],"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."]}