{"id":"CVE-2026-107336","aliases":["EUVD-2026-95115","GHSA-7j32-cf27-cp6h","GHSA-c366-pv2g-9685"],"status":"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.","severity":{"version":"3.1","score":6.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N","level":"medium","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-12","score":0.00241,"percentile":0.15398,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":false},"cwes":["CWE-290","CWE-441","CWE-863"],"published":"2026-10-08T17:20:46Z","modified":"2026-10-28T02:30:21Z","products":[{"vendor":"cisa","product":"malcolm"},{"vendor":"cisagov","product":"malcolm"}],"references":[{"url":"https://github.com/cisagov/Malcolm/security/advisories/GHSA-7j32-cf27-cp6h","tags":["advisory"]},{"url":"https://github.com/cisagov/CSAF/blob/develop/csaf_files/OT/white/2026/icsa-26-280-01.json","tags":["government-resource","web"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-107336","tags":["advisory"]},{"url":"https://github.com/advisories/GHSA-c366-pv2g-9685"},{"url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/107xxx/CVE-2026-107336.json","tags":["advisory"]}],"sources":{"cve":[{"id":"CVE-2026-107336","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.","status":"published","published":"2026-10-08T17:20:46.517Z","modified":"2026-10-14T19:39:35.096Z","cvss":[{"version":"3.1","score":6.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N","level":"medium","assessor":"cna"}],"cwes":["CWE-290","CWE-441","CWE-863"],"updated_at":"2026-11-02T13:45:14.072357Z"}],"euvd":[{"id":"EUVD-2026-95115","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.","status":"published","published":"2026-10-08T17:20:46Z","modified":"2026-10-14T19:39:35Z","cvss":[{"version":"3.1","score":6.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N","level":"medium"}],"updated_at":"2026-11-02T17:27:12.80866Z"}],"ghsa":[{"id":"GHSA-c366-pv2g-9685","title":"Malcolm's front nginx reverse proxy defines a \"Dashboards → Arkime shortcut\" location using a...","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.","status":"published","published":"2026-10-08T18:32:29Z","modified":"2026-10-08T18:32:39Z","cvss":[{"version":"3.1","score":6.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N","level":"medium"}],"cwes":["CWE-290"],"updated_at":"2026-11-02T15:12:57.86261Z"}],"nvd":[{"id":"CVE-2026-107336","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.","status":"published","published":"2026-10-08T18:17:20.177Z","modified":"2026-10-08T21:03:43.847Z","cvss":[{"version":"3.1","score":6.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N","level":"medium","assessor":"secondary"}],"cwes":["CWE-290","CWE-441","CWE-863"],"updated_at":"2026-11-02T14:12:55.142936Z"}],"osv":[{"id":"CVE-2026-107336","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.","status":"published","published":"2026-10-08T17:20:46.517Z","modified":"2026-10-28T02:30:21.869275784Z","cvss":[{"version":"3.1","score":6.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N","level":"medium"}],"cwes":["CWE-290","CWE-441","CWE-863"],"updated_at":"2026-11-02T15:44:54.933106Z"}]}}