Linux Distros Unpatched Vulnerability : CVE-2023-54397

critical Nessus Plugin ID 346310

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.

- Tornado before 6.3.3 contains an HTTP request smuggling vulnerability due to improper parsing of Content- Length headers accepting non-standard characters. Attackers can send crafted HTTP requests with these characters to bypass proxy validation and smuggle requests when deployed behind certain proxies.
(CVE-2023-54397)

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

Solution

There is no known solution at this time.

See Also

https://security-tracker.debian.org/tracker/CVE-2023-54397

https://ubuntu.com/security/CVE-2023-54397

Plugin Details

Severity: Critical

ID: 346310

File Name: unpatched_CVE_2023_54397.nasl

Version: 1.2

Type: Local

Agent: unix

Family: Misc.

Published: 9/16/2026

Updated: 9/17/2026

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: 5.9

Percentile: 96.26

CVSS v2

Risk Factor: Medium

Base Score: 6.1

Temporal Score: 5.2

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

CVSS Score Source: CVE-2023-54397

CVSS v3

Risk Factor: High

Base Score: 7.5

Temporal Score: 6.9

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

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

CVSS v4

Risk Factor: Critical

Base Score: 9

Threat Score: 6.5

Threat Vector: CVSS:4.0/E:U

Vector: CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:L/VI:H/VA:N/SC:L/SI:H/SA:N

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, cpe:/o:debian:debian_linux:12.0, p-cpe:/a:canonical:ubuntu_linux:python-tornado, p-cpe:/a:debian:debian_linux:python-tornado

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: 9/15/2026

Reference Information

CVE: CVE-2023-54397