Linux Distros Unpatched Vulnerability : CVE-2026-23950

high Nessus Plugin ID 293776

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.

- node-tar,a Tar for Node.js, has a race condition vulnerability in versions up to and including 7.5.3. This is due to an incomplete handling of Unicode path collisions in the `path-reservations` system. On case- insensitive or normalization-insensitive filesystems (such as macOS APFS, In which it has been tested), the library fails to lock colliding paths (e.g., `` and `ss`), allowing them to be processed in parallel.
This bypasses the library's internal concurrency safeguards and permits Symlink Poisoning attacks via race conditions. The library uses a `PathReservations` system to ensure that metadata checks and file operations for the same path are serialized. This prevents race conditions where one entry might clobber another concurrently. This is a Race Condition which enables Arbitrary File Overwrite. This vulnerability affects users and systems using node-tar on macOS (APFS/HFS+). Because of using `NFD` Unicode normalization (in which `` and `ss` are different), conflicting paths do not have their order properly preserved under filesystems that ignore Unicode normalization (e.g., APFS (in which `` causes an inode collision with `ss`)). This enables an attacker to circumvent internal parallelization locks (`PathReservations`) using conflicting filenames within a malicious tar archive. The patch in version 7.5.4 updates `path-reservations.js` to use a normalization form that matches the target filesystem's behavior (e.g., `NFKD`), followed by first `toLocaleLowerCase('en')` and then `toLocaleUpperCase('en')`.
As a workaround, users who cannot upgrade promptly, and who are programmatically using `node-tar` to extract arbitrary tarball data should filter out all `SymbolicLink` entries (as npm does) to defend against arbitrary file writes via this file system entry name collision issue. (CVE-2026-23950)

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-2026-23950

https://security-tracker.debian.org/tracker/CVE-2026-23950

https://ubuntu.com/security/CVE-2026-23950

Plugin Details

Severity: High

ID: 293776

File Name: unpatched_CVE_2026_23950.nasl

Version: 1.5

Type: local

Agent: unix

Family: Misc.

Published: 1/20/2026

Updated: 2/10/2026

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

Risk Information

VPR

Risk Factor: Medium

Score: 6.6

CVSS v2

Risk Factor: Medium

Base Score: 4.4

Temporal Score: 3.7

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

CVSS Score Source: CVE-2026-23950

CVSS v3

Risk Factor: High

Base Score: 8.8

Temporal Score: 8.1

Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:H/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:24.04:-:lts, p-cpe:/a:redhat:enterprise_linux:tdx-qgs, cpe:/o:debian:debian_linux:12.0, p-cpe:/a:canonical:ubuntu_linux:node-tar, p-cpe:/a:redhat:enterprise_linux:sgx-pckid-tool, cpe:/o:canonical:ubuntu_linux:25.10, cpe:/o:redhat:enterprise_linux:9, cpe:/o:canonical:ubuntu_linux:18.04:-:lts, p-cpe:/a:redhat:enterprise_linux:sgx-libs, cpe:/o:redhat:enterprise_linux:10, cpe:/o:debian:debian_linux:13.0, cpe:/o:canonical:ubuntu_linux:14.04:-:lts, p-cpe:/a:redhat:enterprise_linux:sgx-common, p-cpe:/a:debian:debian_linux:node-tar, cpe:/o:canonical:ubuntu_linux:16.04:-:lts, cpe:/o:canonical:ubuntu_linux:22.04:-:lts, p-cpe:/a:redhat:enterprise_linux:sgx-mpa

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

Exploit Ease: No known exploits are available

Reference Information

CVE: CVE-2026-23950