Vulnerability · Published Sep 11, 2026 · Assigned by icscert

CVE-2026-90449Missing Authentication for Critical Function in Malcolm

Medium 6.5

In plain English

A medium-severity missing authentication 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 10% of all known vulnerabilities).

Severity (CVSS 3.1)6.5Medium

Exploit odds (30 days)0.2%top 89.9% of all CVEs

Exploited in the wildNo reportsCISA SSVC: none

Attack toolingNoneno public tooling known

Official description

When a particular authentication mode is configured, the reverse proxy forwards requests for a bundled third-party administrative interface directly to that interface without applying the gateway's own authentication requirement first. All access control for this administrative interface, which manages the credential store used to gate every other service in the deployment, is delegated entirely to that third-party interface's own login mechanism. Any authentication weakness in that bundled interface would compromise the credential store protecting the rest of the deployment.

Affected products (as reported)

Vendor	Product	Versions
CISA	Malcolm	0 – before v26.06.0

Weakness: CWE-306 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N

References

https://raw.githubusercontent.com/cisagov/CSAF/develop/csaf_files/OT/white/2026/icsa-26-254-01.json government-resource, vendor-advisory
https://www.cisa.gov/news-events/ics-advisories/icsa-26-254-01