Linux Distros Unpatched Vulnerability : CVE-2026-93582

critical Nessus Plugin ID 365659

Synopsis

The Linux/Unix host has one or more packages installed with a vulnerability that the vendor indicates will not be patched.

Description

The Linux/Unix host has one or more packages installed that are impacted by a vulnerability without a vendor supplied patch available.

- 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 does not perform an additional password verification. An attacker may therefore authenticate through the Generic Interface as an existing agent or customer user without knowing the corresponding credentials. The resulting privileges depend on the account being impersonated. Successful exploitation may allow access to confidential information and modification of data or configuration with the permissions of the affected user. Exploitation requires HTTP Basic Authentication to be configured as an authentication backend and a web server environment in which attacker-controlled HTTP headers are exposed through the corresponding HTTP_* environment variables. OTRS 7 and later are not affected by this attack vector due to the use of Mojolicious/Hypnotoad and does not expose arbitrary request headers through %ENV in the manner required for exploitation. The supported REMOTE_USER mechanism additionally requires validation through the configured SSO shared secret. The unused HTTP_REMOTE_USER fallback has nevertheless been removed as a security-hardening measure. Please note that ((OTRS)) Community Edition 6.x and before are vulnerable.
Products based on the ((OTRS)) Community Edition also very likely to be affected (CVE-2026-93582)

Note that Nessus relies on the presence of the package as reported by the vendor.

Solution

There is no known solution at this time.

Plugin Details

Severity: Critical

ID: 365659

File Name: unpatched_CVE_2026_93582.nasl

Version: 1.2

Type: Local

Agent: unix

Family: Misc.

Published: 10/14/2026

Updated: 10/15/2026

Supported Sensors: Frictionless Assessment AWS, Frictionless Assessment Azure, Frictionless Assessment Agent, Nessus Agent, Agentless Assessment, Tenable Cloud Security, Tenable Self-Hosted Container Security, Nessus

Risk Information

VPR

Risk Factor: Medium

Score: 4.5

Percentile: 57.8

CVSS v2

Risk Factor: High

Base Score: 9.7

Temporal Score: 8.2

Vector: CVSS2#AV:N/AC:L/Au:N/C:C/I:C/A:P

CVSS Score Source: CVE-2026-93582

CVSS v3

Risk Factor: Critical

Base Score: 9.4

Temporal Score: 8.6

Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:L

Temporal Vector: CVSS:3.0/E:U/RL:U/RC:C

Vulnerability Information

CPE: cpe:/o:canonical:ubuntu_linux:16.04:-:lts, cpe:/o:canonical:ubuntu_linux:18.04:-:lts, cpe:/o:canonical:ubuntu_linux:20.04:-:lts, cpe:/o:canonical:ubuntu_linux:22.04:-:lts, cpe:/o:canonical:ubuntu_linux:24.04:-:lts, cpe:/o:canonical:ubuntu_linux:26.04:-:lts, p-cpe:/a:canonical:ubuntu_linux:otrs2, p-cpe:/a:canonical:ubuntu_linux:znuny

Required KB Items: Host/local_checks_enabled, Host/cpu, global_settings/vendor_unpatched, Host/OS/identifier

Exploit Ease: No known exploits are available

Vulnerability Publication Date: 10/12/2026

Reference Information

CVE: CVE-2026-93582

Detections

Analytics