CVE-2026-23950

Fixed in a distro release EPSS <1%CVSS 8.8

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., `ß` 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 `ß` and `ss` are different), conflicting paths do not have their order properly preserved under filesystems that ignore Unicode normalization (e.g., APFS (in which `ß` 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.

Published 2026-01-20 · CVE record · OSV

Products: isaacs node-tar, Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 9, Red Hat OpenShift Dev Spaces 3.27, Red Hat Trusted Artifact Signer 1.2, Red Hat Trusted Artifact Signer 1.3, Red Hat Confidential Compute Attestation, Red Hat Cryostat 4, Logging Subsystem for Red Hat OpenShift, Red Hat Migration Toolkit for Containers, Red Hat Multicluster Engine for Kubernetes, Red Hat Network Observability Operator, Red Hat Node HealthCheck Operator, Red Hat OpenShift Lightspeed, Red Hat OpenShift Pipelines, Red Hat OpenShift Serverless, Red Hat 3scale API Management Platform 2, Red Hat Advanced Cluster Management for Kubernetes 2, Red Hat AMQ Broker 7, Red Hat Ansible Automation Platform 2, Red Hat build of Apache Camel - HawtIO 4, Red Hat Connectivity Link 1, Red Hat Developer Hub, Red Hat Enterprise Linux 6, Red Hat Enterprise Linux 7, Red Hat Enterprise Linux 8, Red Hat Enterprise Linux AI (RHEL AI) 3, Red Hat Fuse 7, Red Hat JBoss Enterprise Application Platform 7, Red Hat JBoss Enterprise Application Platform 8, Red Hat JBoss Enterprise Application Platform Expansion Pack, Red Hat OpenShift AI (RHOAI), Red Hat OpenShift Container Platform 4, Red Hat Openshift Data Foundation 4, Red Hat OpenShift GitOps, Red Hat Process Automation 7, Red Hat Quay 3, Red Hat Satellite 6, Red Hat Single Sign-On 7

Fixed upstream

Distro releases