{"id":"CVE-2026-63177","state":"PUBLISHED","title":"Malcolm Vulnerable to Authorization Bypass via URI Normalization Differential in Nginx Lua RBAC","description":"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.","publishedAt":"2026-08-11T20:30:57.901Z","updatedAt":"2026-10-02T20:27:08.611Z","severity":{"score":7.1,"label":"High","version":"4.0","vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:L/VA:N/SC:N/SI:N/SA:N","source":"icscert"},"assigner":"GitHub_M","products":["cisagov Malcolm"],"affected":[{"vendor":"cisagov","product":"Malcolm","defaultStatus":"unaffected","versions":[{"version":"< 26.07.0","status":"affected"},{"version":"26.07.0","status":"unaffected"}]}],"references":["https://github.com/cisagov/Malcolm/security/advisories/GHSA-m5fr-rv3h-xg2r","https://github.com/cisagov/Malcolm/releases/tag/v26.07.0","https://www.cisa.gov/news-events/ics-advisories/icsa-26-230-01","https://github.com/cisagov/CSAF/blob/develop/csaf_files/OT/white/2026/icsa-26-230-01.json"],"weaknesses":["CWE-863"],"ingestedAt":"2026-10-29T20:12:41.951Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/63xxx/CVE-2026-63177.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-63177","state":"PUBLISHED","datePublished":"2026-08-11T20:30:57.901Z","dateUpdated":"2026-10-02T20:27:08.611Z","assignerShortName":"GitHub_M","assignerOrgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateReserved":"2026-07-15T22:13:00.720Z"},"containers":{"cna":{"title":"Malcolm Vulnerable to Authorization Bypass via URI Normalization Differential in Nginx Lua RBAC","descriptions":[{"lang":"en","value":"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."}],"affected":[{"vendor":"cisagov","product":"Malcolm","defaultStatus":"unaffected","versions":[{"version":"< 26.07.0","status":"affected"},{"version":"26.07.0","status":"unaffected"}]}],"references":[{"url":"https://github.com/cisagov/Malcolm/security/advisories/GHSA-m5fr-rv3h-xg2r","name":"https://github.com/cisagov/Malcolm/security/advisories/GHSA-m5fr-rv3h-xg2r","tags":["x_refsource_CONFIRM"]},{"url":"https://github.com/cisagov/Malcolm/releases/tag/v26.07.0","name":"https://github.com/cisagov/Malcolm/releases/tag/v26.07.0","tags":["x_refsource_MISC"]},{"url":"https://www.cisa.gov/news-events/ics-advisories/icsa-26-230-01"},{"url":"https://github.com/cisagov/CSAF/blob/develop/csaf_files/OT/white/2026/icsa-26-230-01.json"}],"metrics":[{"format":"CVSS","scenarios":[{"lang":"en","value":"GENERAL"}],"cvssV3_1":{"version":"3.1","attackVector":"NETWORK","attackComplexity":"LOW","privilegesRequired":"LOW","userInteraction":"NONE","scope":"UNCHANGED","confidentialityImpact":"HIGH","integrityImpact":"LOW","availabilityImpact":"NONE","baseSeverity":"HIGH","baseScore":7.1,"vectorString":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:L/A:N"}},{"format":"CVSS","scenarios":[{"lang":"en","value":"GENERAL"}],"cvssV4_0":{"attackVector":"NETWORK","attackComplexity":"LOW","attackRequirements":"NONE","privilegesRequired":"LOW","userInteraction":"NONE","vulnConfidentialityImpact":"HIGH","subConfidentialityImpact":"NONE","vulnIntegrityImpact":"LOW","subIntegrityImpact":"NONE","vulnAvailabilityImpact":"NONE","subAvailabilityImpact":"NONE","exploitMaturity":"NOT_DEFINED","Safety":"NOT_DEFINED","Automatable":"NOT_DEFINED","Recovery":"NOT_DEFINED","valueDensity":"NOT_DEFINED","vulnerabilityResponseEffort":"NOT_DEFINED","providerUrgency":"NOT_DEFINED","version":"4.0","baseSeverity":"HIGH","baseScore":7.1,"vectorString":"CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:L/VA:N/SC:N/SI:N/SA:N"}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-863","lang":"en","description":"CWE-863: Incorrect Authorization","type":"CWE"}]}],"providerMetadata":{"shortName":"icscert","orgId":"7d14cffa-0d7d-4270-9dc0-52cabd5a23a6","dateUpdated":"2026-10-02T20:27:08.611Z"},"solutions":[{"lang":"en","value":"Malcolm version 26.07.0 addresses these issues. For more information, see  https://github.com/cisagov/Malcolm/pull/1043","supportingMedia":[{"type":"text/html","base64":false,"value":"Malcolm version 26.07.0 addresses these issues. For more information, see&nbsp;<a href=\"https://github.com/cisagov/Malcolm/pull/1043\">https://github.com/cisagov/Malcolm/pull/1043</a>"}]}],"credits":[{"lang":"en","value":"pavanchow reported this vulnerability to CISA.","type":"finder"}],"source":{"advisory":"GHSA-m5fr-rv3h-xg2r","discovery":"EXTERNAL"},"x_generator":{"engine":"Vulnogram 1.0.5"}},"adp":[{"title":"CISA ADP Vulnrichment","metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-08-12T22:07:37.481958Z","id":"CVE-2026-63177","options":[{"Exploitation":"none"},{"Automatable":"no"},{"Technical Impact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-08-12T22:12:55.745Z"}}]}}}