CVE-2026-107336: medium-severity vulnerability in CISA Malcolm
Authentication Bypass by Spoofing in Malcolm
Published · Updated
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13Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 6.5epss 0.2%
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.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N
Affected products
CISA · MalcolmRelated CVEs — CISA Malcolm
In the same product, most dangerous first.
CVE-2026-107333HIGHIncorrect Authorization in MalcolmEPSS 1.2%CVE-2026-107335MEDIUMImproper Handling of Highly Compressed Data in MalcolmEPSS 0.5%CVE-2026-107362HIGHServer-Side Request Forgery in MalcolmEPSS 0.3%CVE-2026-90445HIGHPath Traversal in MalcolmEPSS 0.3%CVE-2026-90444HIGHOS Command Injection in MalcolmEPSS 0.3%CVE-2026-90456CRITICALUse of default credentials in MalcolmEPSS 0.3%