Security Digest · Vulnerability record
CVE-2026-101894: @xhmikosr/decompress: Path traversal via symlink chain
The decompress package for Node.js extracts archives.
CVSS 9.1 Critical EPSS 0.8% · p57
Should you act?
Critical and remotely reachable
No known exploitation yet, but it is network-reachable without credentials. This signal is computed from CISA KEV, EPSS and CVSS data; it is not an editorial verdict.
- No confirmed exploitation. It is not in CISA’s KEV catalog and CISA’s SSVC assessment records no known exploitation. That can change quickly after a public write-up; re-check if you are affected.
- EPSS 0.8%, percentile 57: FIRST’s model estimates a 0.8% chance of exploitation activity in the next 30 days, higher than 57% of all scored CVEs (moderate). EPSS is a probability, not a verdict.
- Remotely reachable with no login and no user interaction. If the vulnerable service is exposed to the internet, prioritize it.
- Only applies if your dependency tree includes
@xhmikosr/decompress(npm) >= 11.0.0, <= 11.1.3, fixed in 11.1.4;@xhmikosr/decompress(npm) <= 10.2.1, fixed in 10.2.2;decompress(npm) <= 4.2.1, no fixed version listed. Check your lockfile, including transitive dependencies.
What it is
The decompress package for Node.js extracts archives. Prior to 10.2.2 and 11.1.4, the default decompress(input, output) API relies on lexical containment checks that do not account for the kernel following a planted symlink chain. An attacker can supply a crafted archive containing chained symlink entries so that a later entry resolves outside the output directory. This allows files outside output to be read or written, and overwriting startup scripts or configuration can lead to remote code execution. The maintained @xhmikosr/decompress package is fixed in 10.2.2 and 11.1.4, but the separately affected unmaintained decompress package remains unpatched through 4.2.1. This vulnerability results from a bypass of the incomplete hardening for CVE-2026-53486. @xhmikosr/decompress is fixed in versions 10.2.2 and 11.1.4.
From the GitHub advisory
Impact
When extracting an untrusted archive with the default decompress(input, output) API, a crafted archive containing a chain of symlink entries can make a later entry resolve outside the output directory. The lexical containment checks pass, but the kernel follows the planted symlinks to a path outside output, letting an attacker write (and read) files outside the intended extraction directory. Overwriting startup scripts or configuration can lead to remote code execution.
This is a bypass of the hardening in GHSA-mp2f-45pm-3cg9. Any application that extracts attacker-controlled archives is affected.
Patches
Fixed in 11.1.4 (latest) and backported to 10.2.2 (release-v10 dist-tag). Upgrade to one of these.
Weakness type: CWE-22, CWE-59.
Product: @xhmikosr/decompress (npm) · Assigned by: GitHub_M · Published: 2026-09-28
Affected and fixed versions
| Ecosystem | Package | Vulnerable | First fixed |
|---|---|---|---|
| npm | @xhmikosr/decompress | >= 11.0.0, <= 11.1.3 | 11.1.4 |
| npm | @xhmikosr/decompress | <= 10.2.1 | 10.2.2 |
| npm | decompress | <= 4.2.1 | none listed |
| Vendor | Product | Affected versions (per CVE record) |
|---|---|---|
| XhmikosR | decompress | < 10.2.2, >= 11.0.0, < 11.1.4 |
| kevva | decompress | <= 4.2.1 |
Severity scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| GitHub_M | 3.1 | 9.1 Critical | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N |
| GitHub | 3.1 | 9.1 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N |
- Attack vector: network (remotely reachable)
- Attack complexity: low
- Privileges required: none (no login)
- User interaction: none
- Scope: unchanged
CVSS measures how bad a flaw is if exploited, not how likely exploitation is. Read it next to the exploitation data below.
Exploitation and urgency
- CISA KEV: not listed (no confirmed in-the-wild exploitation known to CISA).
- CISA SSVC assessment: exploitation none, automatable yes, technical impact total.
- FIRST EPSS (model of 2026-10-21): 0.81% probability of exploitation activity in the next 30 days; percentile 57.
Timeline
- — CVE record last updated
- — CVE record published by GitHub_M
- — GitHub-reviewed advisory GHSA-hrh2-vp3x-79xf published (critical)
Sources and references
Original sources first. Version and fix details should always be confirmed against the vendor or project advisory.
Vulnerability records
- GitHub Advisory GHSA-hrh2-vp3x-79xf github.com
- CVE.org record CVE-2026-101894 cve.org
- NVD entry CVE-2026-101894 nvd.nist.gov
Other references from the CVE record and advisory
- github.com github.com
- github.com github.com
- github.com github.com
- github.com github.com
- github.com github.com