Linux Distros Unpatched Vulnerability : CVE-2026-103503

medium Nessus Plugin ID 366672

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.

- Improper Certificate Validation vulnerability in hexpm hex allows an attacker who can intercept HTTPS connections, and holds a certificate for a Hex host issued by a CA in Hex's bundled CA store, to impersonate that host to users who set cacerts_path to a CA store that leaves that CA out. cacerts_path (HEX_CACERTS_PATH) is documented as the path to the CA certificate store, used instead of the CA bundle that ships with Hex. Hex.HTTP.SSL.ssl_opts/1 passes the configured store as the cacerts option, but builds the partial_chain callback from the bundled store whether cacerts_path is set or not.
Hex.HTTP.SSL.partial_chain/2 accepts a server chain when any certificate in it has the same public key as a bundled CA certificate, so a chain that leads to a bundled CA passes verification although the configured store doesn't contain that CA. Hostname verification still applies. This issue affects hex:
from 0.20.2 before 2.5.2. (CVE-2026-103503)

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-2026-103503

Plugin Details

Severity: Medium

ID: 366672

File Name: unpatched_CVE_2026_103503.nasl

Version: 1.1

Type: Local

Agent: unix

Family: Misc.

Published: 10/16/2026

Updated: 10/16/2026

Supported Sensors: Nessus Agent, Nessus

Risk Information

VPR

Risk Factor: Low

Score: 3.5

Percentile: 51.44

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-2026-103503

CVSS v3

Risk Factor: High

Base Score: 8.2

Temporal Score: 7.5

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

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

CVSS v4

Risk Factor: Medium

Base Score: 5.9

Threat Score: 2.1

Threat Vector: CVSS:4.0/E:U

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

Vulnerability Information

CPE: cpe:/o:debian:debian_linux:13.0, cpe:/o:debian:debian_linux:14.0, p-cpe:/a:debian:debian_linux:erlang-hex

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-2026-103503