Your RSA-2048 keys break in 2030. Find every one of them before attackers do.
💎
💎 RubyGems
Not in CISA KEV
CRITICAL severity

Rubyzip gem contains a Directory Traversal vulnerability in zip file componentGHSA-vqcq-mrmw-mcmg

CRITICAL

GHSA-vqcq-mrmw-mcmg is a critical-severity (CVSS 9.8) CWE-59 vulnerability in rubyzip. 1 public exploit reference exists, so weaponization risk is real. A fix is available for rubyzip — see the affected versions and patch details below.

Also known asCVE-2018-1000544
Published
Updated
Affected
1 pkg
Patched
1 / 1
Exploits
1 known
Exploitation data as of Oct 23, 2026 · OSV.dev, NVD, FIRST.org (EPSS)

EPSS Exploitation Probability

via FIRST.org ↗
4.4%probability of exploitation in next 30 days
Lower Risk0.00%
Lower risk than most CVEs91th percentile — riskier than 91% of all scored CVEsHighest risk
0.00%1.93%3.85%5.78%0.7%4.4%Apr 26Aug 26Oct 26

Probability of exploitation in the next 30 days, from FIRST.org EPSS.

How urgent is this, really

GHSA-vqcq-mrmw-mcmg by exploitation likelihood (EPSS) against impact (CVSS). Outside the shaded patch-first corner.

Where this sits among everything scored

Of 394,803 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Counts from FIRST.org, log-scaled.

Real-World Exposure

1 pkg affected
💎rubyzip

Real-time download stats are indexed for npm and PyPI packages. This vulnerability affects RubyGems packages — download data is not available via public APIs for these ecosystems.

Description

rubyzip gem rubyzip version 1.2.1 and earlier contains a Directory Traversal vulnerability in Zip::File component that can result in write arbitrary files to the filesystem. This attack appear to be exploitable via If a site allows uploading of .zip files , an attacker can upload a malicious file that contains symlinks or files with absolute pathnames "../" to write arbitrary files to the filesystem..

This is similar to CVE-2017-5946 which was patched in 1.2.1 but the fix in that case was incomplete.

Affected Packages

1 total 1 fixed
EcosystemPackageVulnerable rangeFix
💎RubyGemsrubyzipall versions1.2.2bundle update rubyzip --conservative

Affected Products

3 products · 4 configurations
OS
debian linuxdebian
2 versions
8.09.0
Application
cloudformsredhat
1 version
4.6
Application
rubyziprubyzip_project
≤ 1.2.1
range
Exploits & PoCs
1

Research use only. For defensive security, authorized penetration testing, and academic research only. Never execute exploit code against systems without explicit written authorization.

rubyzip gem rubyzip version 1.2.1 and earlier contains a Directory Trave…

github.comNVDAug 2020

Detection & mitigation playbook

Open-source dependency

  1. Detect

    Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for rubyzip, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.

  2. Fix

    Update rubyzip to 1.2.2 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-vqcq-mrmw-mcmg is resolved across your whole dependency graph.

  3. Workarounds

    Treat uploaded files as untrusted until proven otherwise: validate the actual content type rather than the supplied extension, store uploads outside the web root on a volume mounted without execute permission, and rename them to server-generated identifiers so an attacker cannot choose the path a request will later resolve.

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.

Red HatModerate
ProductFixed inAdvisory
CloudForms Management Engine 5.9ansible-tower-0:3.2.7-1.el7atRHSA-2018:3466

Frequently Asked Questions

rubyzip gem rubyzip version 1.2.1 and earlier contains a Directory Traversal vulnerability in Zip::File component that can result in write arbitrary files to the filesystem. This attack appear to be exploitable via If a site allows uploading of .zip files , an attacker can upload a malicious file that contains symlinks or files with absolute pathnames "../" to write arbitrary files to the filesystem.. This is similar to CVE-2017-5946 which was patched in 1.2.1 but the fix in that case was incomplete.
O3 Security · Impact-Aware SCA

Is GHSA-vqcq-mrmw-mcmg in your dependencies?

Find it across RubyGems, including transitive dependencies.

Scan my dependencies How O3 SCA works
Rubyzip gem contains a Directory Traversal vulnerability…