{"cve":"CVE-2026-55149","nvd":{"published":"2026-09-15T17:17:21.893","modified":"2026-09-30T17:51:56.193","status":"Deferred","description":"Vouch Proxy is an SSO and OAuth/OIDC login solution for Nginx using the auth_request module. Prior to 0.48.0, Cookie in pkg/cookie/cookie.go parses the total part count from an attacker-controlled multipart cookie name and passes the value to make([]string, numParts) without checking that the value is positive or reasonably bounded. Requests to /validate and /_external-auth-:id reach JWTCacheHandler in pkg/jwtmanager/jwtcache.go, FindJWT in pkg/jwtmanager/jwtmanager.go, and the vulnerable cookie reassembly before JWT validation, so no account or valid session is required. A cookie name such as VouchCookie_1of10000000000 causes an attempted slice allocation of roughly 160 GB and a fatal Go runtime out-of-memory condition, allowing one request to crash the authentication proxy and repeated requests to sustain unavailability. This vulnerability is fixed in 0.48.0.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","score":7.5},"cwes":["CWE-789"],"references":["https://github.com/vouch/vouch-proxy/commit/fa18ce30ba50a4863a436acad044c22965329c4f","https://github.com/vouch/vouch-proxy/releases/tag/v0.48.0","https://github.com/vouch/vouch-proxy/security/advisories/GHSA-qqff-5854-px68","https://github.com/vouch/vouch-proxy/security/advisories/GHSA-qqff-5854-px68"],"products":[],"source":"nvd","synced_at":"2026-10-19T22:53:43.293028046+00:00"},"epss":{"cve":"CVE-2026-55149","score":0.00718,"percentile":0.53559,"date":"2026-10-25"},"kev":null,"osv":[{"id":"GHSA-qqff-5854-px68","url":"https://osv.dev/vulnerability/GHSA-qqff-5854-px68","summary":"vouch-proxy has an Unbounded Multipart Cookie Allocation DoS","modified":"2026-08-26T01:21:46.632746820Z","packages":[{"ecosystem":"Go","name":"github.com/vouch/vouch-proxy","purl":"pkg:golang/github.com/vouch/vouch-proxy","ranges":["<0.48.0"],"fixed":["0.48.0"]}]},{"id":"GO-2026-6260","url":"https://osv.dev/vulnerability/GO-2026-6260","summary":"vouch-proxy has an Unbounded Multipart Cookie Allocation DoS in github.com/vouch/vouch-proxy","modified":"2026-08-26T01:21:40.783300254Z","packages":[{"ecosystem":"Go","name":"github.com/vouch/vouch-proxy","purl":"pkg:golang/github.com/vouch/vouch-proxy","ranges":["<0.48.0"],"fixed":["0.48.0"]}]}],"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."]}