Vulnerability · Published Sep 11, 2026 · Assigned by icscert

CVE-2026-90450Incorrect Authorization in Malcolm

Medium 4.3

In plain English

A medium-severity incorrect authorization 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 7% of all known vulnerabilities).

Severity (CVSS 3.1)4.3Medium

Exploit odds (30 days)0.2%top 92.6% of all CVEs

Exploited in the wildNo reportsCISA SSVC: none

Attack toolingNoneno public tooling known

Official description

The application's role-authorization lookup defaults to granting access when a request handler's name is not present in its table of role requirements, rather than defaulting to deny. Any request handler that is not explicitly registered in this table is reachable by any authenticated user regardless of their assigned role, and any newly added handler is fail-open by default until explicitly added to the table.

Affected products (as reported)

Vendor	Product	Versions
CISA	Malcolm	0 – before v26.06.0

Weakness: CWE-863 · Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/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