Linux Distros Unpatched Vulnerability : CVE-2026-43000

medium Nessus Plugin ID 317601

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.

- An issue was discovered in OpenStack Keystone before 29.0.2. When combined with an application credential impersonation vulnerability, an attacker with the member role on a project can escalate to admin by chaining unrestricted application credentials with Keystone trusts. The impersonated token carries the victim's identity, which passes the trustor validation check. Keystone then validates the delegated roles against the victim's actual role assignments in the database, not the roles on the requesting token. This allows the attacker to create a trust delegating the victim's admin role to themselves. The trust persists independently, and additional trusts and application credentials can be created to maintain access. All actions are logged under the victim's identity. (CVE-2026-43000)

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-2026-43000

https://ubuntu.com/security/CVE-2026-43000

Plugin Details

Severity: Medium

ID: 317601

File Name: unpatched_CVE_2026_43000.nasl

Version: 1.2

Type: Local

Agent: unix

Family: Misc.

Published: 5/29/2026

Updated: 5/29/2026

Supported Sensors: Agentless Assessment, Frictionless Assessment Agent, Frictionless Assessment AWS, Frictionless Assessment Azure, Nessus Agent, Nessus

Risk Information

VPR

Risk Factor: Medium

Score: 4.9

CVSS v2

Risk Factor: Medium

Base Score: 4.9

Temporal Score: 4.2

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

CVSS Score Source: CVE-2026-43000

CVSS v3

Risk Factor: Medium

Base Score: 6

Temporal Score: 5.5

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

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

Vulnerability Information

CPE: cpe:/o:debian:debian_linux:11.0, cpe:/o:canonical:ubuntu_linux:20.04:-:lts, cpe:/o:canonical:ubuntu_linux:25.10, cpe:/o:canonical:ubuntu_linux:24.04:-:lts, cpe:/o:canonical:ubuntu_linux:16.04:-:lts, cpe:/o:canonical:ubuntu_linux:18.04:-:lts, p-cpe:/a:canonical:ubuntu_linux:keystone, p-cpe:/a:debian:debian_linux:keystone, cpe:/o:debian:debian_linux:13.0, cpe:/o:canonical:ubuntu_linux:22.04:-:lts, cpe:/o:debian:debian_linux:14.0, cpe:/o:debian:debian_linux:12.0, cpe:/o:canonical:ubuntu_linux:26.04:-:lts

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

Exploit Ease: No known exploits are available

Vulnerability Publication Date: 5/28/2026

Reference Information

CVE: CVE-2026-43000