{"id":"CVE-2026-107336","state":"PUBLISHED","title":"Authentication Bypass by Spoofing in Malcolm","description":"Malcolm's front nginx reverse proxy defines a \"Dashboards → Arkime shortcut\" location using a case-insensitive regex matcher but a case-sensitive rewrite. A request whose path segment is not exact-lowercase (for example /IDDASH2ARK/...) enters the location (the matcher fires) but evades the rewrite (no redirect is issued), so nginx falls through to the location's proxy_pass to the Arkime backend. That location is the one proxied location in the shipped config that does not include the per-location authentication file, so the request reaches Arkime unauthenticated. The same location also forwards a client-supplied X-Forwarded-User header un-overwritten, and Arkime is configured to trust X-Forwarded-User as the authenticated username — so an unauthenticated network caller can reach the Arkime backend while supplying a forged, auto-provisioned identity.","publishedAt":"2026-10-08T17:20:46.517Z","updatedAt":"2026-10-14T19:39:35.096Z","severity":{"score":6.5,"label":"Medium","version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N","source":"icscert"},"assigner":"icscert","products":["CISA Malcolm"],"affected":[{"vendor":"CISA","product":"Malcolm","defaultStatus":"unaffected","versions":[{"version":"0","status":"affected","lessThanOrEqual":"26.07.1","versionType":"custom"},{"version":"26.08.0","status":"unaffected"}]}],"references":["https://github.com/cisagov/Malcolm/security/advisories/GHSA-7j32-cf27-cp6h","https://github.com/cisagov/CSAF/blob/develop/csaf_files/OT/white/2026/icsa-26-280-01.json"],"weaknesses":["CWE-290","CWE-441","CWE-863"],"ingestedAt":"2026-10-29T20:10:23.711Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/107xxx/CVE-2026-107336.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-107336","state":"PUBLISHED","datePublished":"2026-10-08T17:20:46.517Z","dateUpdated":"2026-10-14T19:39:35.096Z","assignerShortName":"icscert","assignerOrgId":"7d14cffa-0d7d-4270-9dc0-52cabd5a23a6","dateReserved":"2026-10-07T18:31:15.966Z"},"containers":{"cna":{"title":"Authentication Bypass by Spoofing in Malcolm","descriptions":[{"lang":"en","value":"Malcolm's front nginx reverse proxy defines a \"Dashboards → Arkime shortcut\" location using a case-insensitive regex matcher but a case-sensitive rewrite. A request whose path segment is not exact-lowercase (for example /IDDASH2ARK/...) enters the location (the matcher fires) but evades the rewrite (no redirect is issued), so nginx falls through to the location's proxy_pass to the Arkime backend. That location is the one proxied location in the shipped config that does not include the per-location authentication file, so the request reaches Arkime unauthenticated. The same location also forwards a client-supplied X-Forwarded-User header un-overwritten, and Arkime is configured to trust X-Forwarded-User as the authenticated username — so an unauthenticated network caller can reach the Arkime backend while supplying a forged, auto-provisioned identity."}],"affected":[{"vendor":"CISA","product":"Malcolm","defaultStatus":"unaffected","versions":[{"version":"0","status":"affected","lessThanOrEqual":"26.07.1","versionType":"custom"},{"version":"26.08.0","status":"unaffected"}]}],"references":[{"url":"https://github.com/cisagov/Malcolm/security/advisories/GHSA-7j32-cf27-cp6h"},{"url":"https://github.com/cisagov/CSAF/blob/develop/csaf_files/OT/white/2026/icsa-26-280-01.json","tags":["government-resource"]}],"metrics":[{"format":"CVSS","scenarios":[{"lang":"en","value":"GENERAL"}],"cvssV3_1":{"version":"3.1","attackVector":"NETWORK","attackComplexity":"LOW","privilegesRequired":"NONE","userInteraction":"NONE","scope":"UNCHANGED","confidentialityImpact":"LOW","integrityImpact":"LOW","availabilityImpact":"NONE","baseSeverity":"MEDIUM","baseScore":6.5,"vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N"}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-290","lang":"en","description":"CWE-290 Authentication bypass by spoofing","type":"CWE"}]},{"descriptions":[{"cweId":"CWE-441","lang":"en","description":"CWE-441 Unintended Proxy or Intermediary","type":"CWE"}]},{"descriptions":[{"cweId":"CWE-863","lang":"en","description":"CWE-863 Incorrect Authorization","type":"CWE"}]}],"providerMetadata":{"shortName":"icscert","orgId":"7d14cffa-0d7d-4270-9dc0-52cabd5a23a6","dateUpdated":"2026-10-14T19:39:35.096Z"},"datePublic":"2026-10-07T19:02:00.000Z","solutions":[{"lang":"en","value":"Update to version v26.08.0","supportingMedia":[{"type":"text/html","base64":false,"value":"Update to version v26.08.0"}]}],"credits":[{"lang":"en","value":"Seth Grover","type":"reporter"},{"lang":"en","value":"Santosh Kumar Puppala","type":"finder"}],"source":{"discovery":"INTERNAL"},"x_generator":{"engine":"Vulnogram 1.0.5"}},"adp":[{"title":"CISA ADP Vulnrichment","metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-10-08T19:07:14.526487Z","id":"CVE-2026-107336","options":[{"Exploitation":"none"},{"Automatable":"yes"},{"Technical Impact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-10-08T19:07:23.845Z"}}]}}}