CVE-2025-48387 — tar-fs
Fix: mafintosh/tar-fs@647447bCVE-2025-48387 is a Path Traversal vulnerability in tar-fs. A fix is available for tar-fs — see the affected versions and patch details below.
tar-fs has issue where extract can write outside the specified dir with a specific tarball
Exploitation Status
No confirmed exploitation observed yet
- CISA assesses this as automatable — exploitation doesn’t require manual, per-target effort, which raises the odds of mass scanning and opportunistic attacks.
- CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.
Exploitation and automatability from CISA’s SSVC triage for CVE-2025-48387.
EPSS Exploitation Probability
EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.
Real-World Exposure
How broadly this vulnerability is actually deployed: weekly install volume shows current usage, and reverse-dependency count shows how many other packages break if it stays unpatched.
tar-fsnpmDescription
Impact
v3.0.8, v2.1.2, v1.16.4 and below
Patches
Has been patched in 3.0.9, 2.1.3, and 1.16.5
Workarounds
You can use the ignore option to ignore non files/directories.
ignore (_, header) {
// pass files & directories, ignore e.g. symlinks
return header.type !== 'file' && header.type !== 'directory'
}
Credit
Thank you Caleb Brown from Google Open Source Security Team for reporting this in detail.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 📦npm | tar-fs | all versions | 1.16.5npm install tar-fs@1.16.5 |
| 📦npm | tar-fs | ≥ 2.0.0&&< 2.1.3 | 2.1.3npm install tar-fs@2.1.3 |
| 📦npm | tar-fs | ≥ 3.0.0&&< 3.0.9 | 3.0.9npm install tar-fs@3.0.9 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for tar-fs, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update tar-fs to 1.16.5 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2025-48387 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like CVE-2025-48387 can be triaged on real exposure rather than presence alone.
Tailored to CVE-2025-48387. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Fixing This On Your OS
If you run this on a Linux distribution, patch through your package manager against the distro's own security advisory below — it tracks the exact backported fix for your release, which can ship on a different timeline (and sometimes a different severity) than the upstream project.
This vulnerability in tar-fs is Important not a moderate flaw, primarily due to its ability to bypass directory confinement during tarball extraction. The core issue—path traversal via crafted archive entries—allows attackers to write files outside the intended extraction directory, potentially overwriting system…
| Product | Fixed in | Advisory |
|---|---|---|
| Red Hat Developer Hub 1.5 | rhdh/rhdh-hub-rhel9:1.5.3-1752159545 | RHSA-2025:10992 |
| Red Hat Developer Hub 1.6 | rhdh/rhdh-hub-rhel9:1.6.2-1750887220 | RHSA-2025:9966 |
| Red Hat Developer Hub 1.7 | rhdh/rhdh-hub-rhel9:1.7.0-1754936470 | RHSA-2025:14090 |
| Red Hat OpenShift Dev Spaces (RHOSDS) 3.23 | devspaces/code-rhel9:3.23-1757618807 | RHSA-2025:15847 |
Frequently Asked Questions
Is CVE-2025-48387 in your dependencies?
O3 Security finds CVE-2025-48387 across npm dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.