Vulnerability · Published Sep 11, 2026 · Assigned by icscert
CVE-2026-90447Authentication Bypass by Spoofing in Malcolm
Medium 6.5
In plain English
A medium-severity authentication bypass by spoofing in Malcolm from CISA. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.2% (higher than 13% of all known vulnerabilities).
Official description
A routing rule selects between two different authentication mechanisms for the same downstream service based on the value of a client-supplied request header, rather than on any property the client cannot control. An authenticated user in possession of a shared service credential can set this header to route around the primary role-based authorization check and reach the alternate path's fixed, elevated role instead. This allows a low-privileged authenticated attacker who knows the shared credential to perform actions reserved for a higher-privileged role.
Affected products (as reported)
Weakness: CWE-290 · Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N