Detections
Analytics

Linux Distros Unpatched Vulnerability : CVE-2026-103399

medium Nessus Plugin ID 353361

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.

 - A flaw was found in SoupServer (libsoup). When an HTTP/1.x client sends a request with Expect:
 100-continue and a request body, and SoupServer returns an early final (non-1xx) response before the body is read, the server neither drains the declared body bytes nor closes the connection. On a keep-alive connection, those leftover bytes are interpreted as a subsequent HTTP request. A remote, unauthenticated attacker can place a complete HTTP request in the body and cause SoupServer to process that smuggled request, leading to unintended request handling. (CVE-2026-103399)

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://access.redhat.com/security/cve/cve-2026-103399

https://security-tracker.debian.org/tracker/CVE-2026-103399

Plugin Details

Severity: Medium

ID: 353361

File Name: unpatched_CVE_2026_103399.nasl

Version: 1.2

Type: Local

Agent: unix

Family: Misc.

Published: 9/30/2026

Updated: 10/1/2026

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: Low

Score: 1.2

Percentile: 0.01

CVSS v2

Risk Factor: Medium

Base Score: 6.4

Temporal Score: 5.4

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

CVSS Score Source: CVE-2026-103399

CVSS v3

Risk Factor: Medium

Base Score: 5.3

Temporal Score: 4.9

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

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

Vulnerability Information

CPE: cpe:/o:centos:centos:7, cpe:/o:centos:centos:8, cpe:/o:debian:debian_linux:12.0, cpe:/o:debian:debian_linux:13.0, cpe:/o:debian:debian_linux:14.0, cpe:/o:redhat:enterprise_linux:10, cpe:/o:redhat:enterprise_linux:7, cpe:/o:redhat:enterprise_linux:8, cpe:/o:redhat:enterprise_linux:9, p-cpe:/a:centos:centos:libsoup-devel, p-cpe:/a:centos:centos:libsoup3-devel, p-cpe:/a:centos:centos:libsoup3-doc, p-cpe:/a:centos:centos:libsoup3, p-cpe:/a:centos:centos:libsoup, p-cpe:/a:debian:debian_linux:libsoup2.4, p-cpe:/a:debian:debian_linux:libsoup3, p-cpe:/a:redhat:enterprise_linux:libsoup-devel, p-cpe:/a:redhat:enterprise_linux:libsoup3-devel, p-cpe:/a:redhat:enterprise_linux:libsoup3-doc, p-cpe:/a:redhat:enterprise_linux:libsoup3, p-cpe:/a:redhat:enterprise_linux:libsoup

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: 9/30/2026

Reference Information

CVE: CVE-2026-103399