{"id":"CVE-2026-63177","summary":"Malcolm Vulnerable to Authorization Bypass via URI Normalization Differential in Nginx Lua RBAC","details":"Malcolm is a network traffic analysis tool suite. Prior to version 26.07.0, role-based access control enforced in the Nginx OpenResty Lua layer evaluates the raw, unnormalized `ngx.var.request_uri`, while Nginx itself routes requests using the normalized path. An authenticated low-privilege user can prepend a traversal segment (for example `/x/../upload/...`) so that Nginx routes the request to a restricted backend while the Lua role check fails to match any rule and falls open, granting access it should deny. Version 26.07.0 fixes the issue.","aliases":["GHSA-m5fr-rv3h-xg2r"],"modified":"2026-08-14T03:52:02.973135654Z","published":"2026-08-11T20:30:57.901Z","database_specific":{"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/63xxx/CVE-2026-63177.json","cna_assigner":"GitHub_M","cwe_ids":["CWE-863"]},"references":[{"type":"WEB","url":"https://github.com/cisagov/Malcolm/releases/tag/v26.07.0"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/63xxx/CVE-2026-63177.json"},{"type":"ADVISORY","url":"https://github.com/cisagov/Malcolm/security/advisories/GHSA-m5fr-rv3h-xg2r"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-63177"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://github.com/cisagov/malcolm","events":[{"introduced":"0"},{"fixed":"551ce2d94052f986a14662aabb85eecfe96d0a30"}],"database_specific":{"extracted_events":[{"introduced":"0"},{"fixed":"26.07.0"}],"source":["AFFECTED_FIELD","REFERENCES"]}}],"versions":["v26.06.1","v26.06.0","v26.05.2","v6.4.2","v6.4.1","v6.4.0","v5.2.4","v5.2.3","v5.2.2","v5.2.1","v3.0.1","v3.0.0","v2.6.1","v2.6.0","v2.5.0","v2.4.2","v2.4.1","v2.4.0.1","v2.4.0","v2.3.0","v2.2.1","v2.2.0","v2.1.1","v2.1.0","v2.0.6","v2.0.5","v2.0.4","v2.0.3","v2.0.2","v2.0.1","v2.0.0","v2.0.0-pre1","v1.8.1","v1.8.0","v1.7.2","v1.7.1a","v1.7.1","v1.7.0","v1.6.0","v1.5.2","v1.5.1","v1.5.0","v1.4.0","v1.3.1","v1.3.0","v1.2.2","v1.2.1","v1.2.0"],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-63177.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:L/A:N"}]}