CVE-2026-107336 (GCVE-0-2026-107336)

Vulnerability from cvelistv5 – Published: 2026-10-08 17:20 – Updated: 2026-10-08 19:07
VLAI
Title
Authentication Bypass by Spoofing in Malcolm
Summary
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
6.5 (Medium)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N
SSVC
Exploitation: none Automatable: yes Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-10-08 19:07 UTC
CWE
  • CWE-290 - Authentication bypass by spoofing
  • CWE-441 - Unintended Proxy or Intermediary
  • CWE-863 - Incorrect Authorization
Assigner
icscert CNA under the icscert root
CNA scorecard C 75/100 over 352 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
CISA Malcolm Affected: 0 , ≤ 26.07.1 (custom)
Unaffected: 26.08.0
guessed Create a notification for this product.
Date Public
2026-10-07 19:02
Credits
Seth Grover
Show details on NVD website
To clipboard 

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