SECURELYN

CVE-2026-93582

The HTTP Basic Authentication modules in ((OTRS)) Community Edition 6 and prior accept the authenticated username from either the REMOTE_USER or HTTP_REMOTE_USER environment variable. In CGI and mod_perl based deployments, HTTP request headers may be mapped to corresponding HTTP_* environment variables. As a result, an unauthenticated remote attacker can supply a crafted Remote-User request header which is exposed to the application as HTTP_REMOTE_USER. When HTTP Basic Authentication is configured as the authentication backend, OTRS trusts this value as an already authenticated username and d…

Scores

9.4
CVSS 9.4 out of 10, critical severity.
0.4%
EPSS 0.4% chance of exploitation in the next 30 days.

The facts

Published
12 October 2026
Last changed
15 October 2026
NVD status
Deferred
Severity
Critical, CVSS 9.4 out of 10 (version 3.1)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:L
Weakness
Known exploited
Not in the CISA Known Exploited Vulnerabilities catalogue in this build.
EPSS
0.4% chance of exploitation activity in the next 30 days (percentile 32).

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References