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Fencer Vulns
high 8.8

CVE-2026-23950 json

node-tar has Race Condition in Path Reservations via Unicode Ligature Collisions on macOS APFS

published 2026-01-20 9 mo ago modified 2026-09-10 1 mo ago also EUVD-2026-3595 , GHSA-r6q2-hw4h-h46w

cvss
8.8
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
0.3%
EPSS 0.3% chance of exploitation in 30 days, percentile 18%
public exploits
0
none known

Summary

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.

Patch / fix

  • npm tar 7.5.4
  • Red Hat Red Hat Enterprise Linux 10 0:2.26-7.el10
  • Red Hat Red Hat Enterprise Linux 9 0:2.26-7.el9
  • Red Hat Red Hat OpenShift Dev Spaces 3.27 1774451954
  • Red Hat Red Hat Trusted Artifact Signer 1.2 1770739056
  • Red Hat Red Hat Trusted Artifact Signer 1.3 1770107452
  • node-tar Debian 13 6.2.1+~cs7.0.8-1+deb13u1
  • node-tar Debian 14 6.2.1+ds1+~cs6.1.13-7

debian advisories DEBIAN-CVE-2026-23950

  • linux-sgx RHEL 9 2.26-7.el9
  • sgx-mpa RHEL 9 2.26-7.el9
  • tdx-qgs RHEL 9 2.26-7.el9
  • sgx-libs RHEL 9 2.26-7.el9
  • sgx-pccs RHEL 9 2.26-7.el9
  • sgx-common RHEL 9 2.26-7.el9
  • sgx-pccs-admin RHEL 9 2.26-7.el9
  • sgx-pckid-tool RHEL 9 2.26-7.el9

red hat advisories RHSA-2026:18868RHSA-2026:18480

  • sgx-mpa AlmaLinux 10 2.26-7.el10
  • tdx-qgs AlmaLinux 10 2.26-7.el10
  • sgx-libs AlmaLinux 10 2.26-7.el10
  • sgx-pccs AlmaLinux 10 2.26-7.el10
  • sgx-common AlmaLinux 10 2.26-7.el10
  • sgx-pccs-admin AlmaLinux 10 2.26-7.el10
  • sgx-pckid-tool AlmaLinux 10 2.26-7.el10
  • sgx-mpa AlmaLinux 9 2.26-7.el9

almalinux advisories ALSA-2026:18480ALSA-2026:18868

  • linux-sgx Rocky Linux 10 2.26-7.el10
  • linux-sgx Rocky Linux 9 2.26-7.el9

rocky linux advisories RLSA-2026:18480RLSA-2026:18868

Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2026-23950 updated cvss 8.8

node-tar: tar: node-tar: Arbitrary file overwrite via Unicode path collision race condition

  • Red Hat Confidential Compute Attestation openshift-sandboxed-containers/osc-pccs
    affected: workaround, no fix available
  • Red Hat Logging Subsystem for Red Hat OpenShift openshift-logging/kibana6-rhel8
    affected: workaround, no fix planned “Will not fix”
  • Red Hat Migration Toolkit for Containers rhmtc/openshift-migration-ui-rhel8 Red Hat Network Observability Operator network-observability/network-observability-console-plugin-rhel9
    affected: workaround, no fix available
  • Red Hat OpenShift Lightspeed openshift-lightspeed/lightspeed-to-dataverse-exporter-rhel9 Red Hat OpenShift Pipelines openshift-pipelines/pipelines-console-plugin-rhel8
    affected: workaround, no fix planned “Will not fix”
  • Red Hat OpenShift Serverless openshift-serverless-1/kn-eventing-integrations-transform-jsonata-rhel9
    affected: workaround, no fix available
  • Red Hat 3scale API Management Platform 2 3scale-amp20/system, 3scale-amp21/system, 3scale-amp22/system, 3scale-amp24/system, 3scale-amp25/system, 3scale-amp26/system, +3 more
    affected: workaround, no fix planned “Will not fix”
  • Red Hat Connectivity Link 1 rhcl-1/rhcl-console-plugin-rhel9
    affected: workaround, no fix available
  • Red Hat Developer Hub 1 rhdh/rhdh-hub-rhel9
    affected: workaround, no fix planned “Will not fix”
show 22 more
  • Red Hat Enterprise Linux 6 tar
    affected: workaround, no fix planned “Out of support scope”
  • Red Hat Enterprise Linux AI (RHEL AI) 3 rhelai3/bootc-cuda-rhel9 Red Hat Fuse 7 io.hawt-project
    affected: workaround, no fix planned “Will not fix”
  • Red Hat OpenShift AI (RHOAI) rhoai/odh-dashboard-rhel8, rhoai/odh-dashboard-rhel9
    affected: workaround, no fix available
  • Red Hat OpenShift Container Platform 4 openshift4/ose-console-rhel9
    affected: workaround, no fix planned “Will not fix”
  • Red Hat Openshift Data Foundation 4 odf4/mcg-core-rhel9, odf4/odf-console-rhel9
    affected: workaround, no fix available
  • Red Hat OpenShift GitOps openshift-gitops-1/argocd-rhel8
    affected: workaround, no fix planned “Will not fix”
  • Red Hat Satellite 6 satellite/iop-remediations-rhel9
    affected: workaround, no fix available
  • Red Hat Enterprise Linux AppStream (v. 9) sgx-mpa 2.26-7.el9, tdx-qgs 2.26-7.el9, sgx-libs 2.26-7.el9, sgx-pccs 2.26-7.el9, linux-sgx 2.26-7.el9, sgx-common 2.26-7.el9, +2 more
    fixed: vendor fix RHSA-2026:18868
  • Red Hat Enterprise Linux AppStream (v. 10) sgx-mpa 2.26-7.el10, tdx-qgs 2.26-7.el10, sgx-libs 2.26-7.el10, sgx-pccs 2.26-7.el10, linux-sgx 2.26-7.el10, sgx-common 2.26-7.el10, +2 more
    fixed: vendor fix RHSA-2026:18480
  • Red Hat OpenShift Dev Spaces 3.27 devspaces 1774451954
    fixed: vendor fix RHSA-2026:6192
  • Red Hat Trusted Artifact Signer 1.2 rhtas 1770739056
    fixed: vendor fix RHSA-2026:2926
  • Red Hat Trusted Artifact Signer 1.3 rhtas 1770107452
    fixed: vendor fix RHSA-2026:2144
  • Red Hat Cryostat 4 io.cryostat-cryostat Red Hat Multicluster Engine for Kubernetes multicluster-engine/console-mce-rhel8, multicluster-engine/console-mce-rhel9
    not affected: component not present
  • Red Hat Node HealthCheck Operator workload-availability/node-remediation-console-rhel9
    not affected: vulnerable code not in execute path
  • Red Hat Advanced Cluster Management for Kubernetes 2 rhacm2/console-rhel9 Red Hat AMQ Broker 7 org.jolokia-jolokia-parent
    not affected: component not present
  • Red Hat Ansible Automation Platform 2 ansible-automation-platform-tech-preview/mcp-server-rhel9
    not affected: vulnerable code not present
  • Red Hat build of Apache Camel - HawtIO 4 io.hawt-project
    not affected: vulnerable code not in execute path
  • Red Hat Enterprise Linux 7 tar
    not affected: vulnerable code not present
  • Red Hat Enterprise Linux 8 npm, tar, nodejs, grafana, mozjs60, nodejs-libs, +17 more Red Hat Enterprise Linux 9 gjs, npm, tar, nodejs, polkit, grafana, +4 more
    not affected: vulnerable code not in execute path
  • Red Hat Enterprise Linux 10 tar, nodejs22, nodejs24
    not affected: component not present
  • Red Hat JBoss Enterprise Application Platform 7 io.hawt-project Red Hat JBoss Enterprise Application Platform 8 io.hawt-project Red Hat JBoss Enterprise Application Platform Expansion Pack io.hawt-project Red Hat OpenShift Container Platform 4 openshift/ose-rhel-coreos-8, openshift/ose-rhel-coreos-9 Red Hat OpenShift Dev Spaces 3.27 devspaces 1773775028, devspaces 1773775064, devspaces 1773775544, devspaces 1774070844, devspaces 1774143680, devspaces 1774155063, +9 more
    not affected: vulnerable code not present
  • Red Hat Process Automation 7 org.uberfire-uberfire-parent
    not affected: component not present

4 more not affected in the full advisory

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

CISA SSVC

Exploitation
none
Automatable
no
Technical impact
partial
Assessed
9 mo ago

Exploit prediction

0.26% chance of exploitation in the next 30 days, higher than 18% of all scored CVEs (FIRST EPSS, 2026-11-08).

Exploits and checks

  • github.com https://github.com/isaacs/node-tar/security/advisories/GHSA-r6q2-hw4h-h46w referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by version score vector
CNA 3.1 8.8 CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:H/A:L
CISA ADP 3.1 8.8 CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:H/A:L
GitHub 3.1 8.8 CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:H/A:L
NVD 3.1 5.9 CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N

Affected packages

ecosystem package affected fixed in
npm tar
<7.5.4
7.5.4

Affected products

  • isaacs node-tar
  • Red Hat Red Hat Enterprise Linux 10
  • Red Hat Red Hat Enterprise Linux 9
  • Red Hat Red Hat OpenShift Dev Spaces 3.27
  • Red Hat Red Hat Trusted Artifact Signer 1.2
  • Red Hat Red Hat Trusted Artifact Signer 1.3
  • Red Hat Confidential Compute Attestation
  • Red Hat Cryostat 4
  • Red Hat 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 Red Hat 3scale API Management Platform 2
  • Red Hat Red Hat Advanced Cluster Management for Kubernetes 2
  • Red Hat Red Hat AMQ Broker 7
  • Red Hat Red Hat Ansible Automation Platform 2
  • Red Hat Red Hat build of Apache Camel - HawtIO 4
  • Red Hat Red Hat Connectivity Link 1
  • Red Hat Red Hat Developer Hub
  • Red Hat Red Hat Enterprise Linux 6
  • Red Hat Red Hat Enterprise Linux 7
  • Red Hat Red Hat Enterprise Linux 8
  • Red Hat Red Hat Enterprise Linux AI (RHEL AI) 3
  • Red Hat Red Hat Fuse 7
  • Red Hat Red Hat JBoss Enterprise Application Platform 7
  • Red Hat Red Hat JBoss Enterprise Application Platform 8
  • Red Hat Red Hat JBoss Enterprise Application Platform Expansion Pack
  • Red Hat Red Hat OpenShift AI (RHOAI)
  • Red Hat Red Hat OpenShift Container Platform 4
  • Red Hat Red Hat Openshift Data Foundation 4
  • Red Hat Red Hat OpenShift GitOps
  • Red Hat Red Hat Process Automation 7
  • Red Hat Red Hat Quay 3
  • Red Hat Red Hat Satellite 6
  • Red Hat Red Hat Single Sign-On 7

Classification

Weakness
  • CWE-176 Improper Handling of Unicode Encoding
  • CWE-352 Cross-Site Request Forgery
  • CWE-367 Time-of-check Time-of-use (TOCTOU) Race Condition

References

Sources

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

CPEs and fixed versions use Anchore's correction of NVD's data: Added CPE configurations because not yet analyzed by NVD.