CVE-2023-40165: rubygems.org is the Ruby community's primary gem (library) hosting service

Q: How do I fix CVE-2023-40165?

rubygems.org: upgrade to 2023-08-14. Exact commands for each OS are on this page.

Q: Is CVE-2023-40165 being exploited?

CVE-2023-40165 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.

Q: What does CVE-2023-40165 affect?

CVE-2023-40165 affects rubygems.org. Severity is high (CVSS 7.4). rubygems.org is the Ruby community's primary gem (library) hosting service. Insufficient input validation allowed malicious actors to replace any uploaded gem version that had a platform, version number, or gem name matching `/-\d/`, perman

Routine

HIGH 7.4UPGRADE

CVE-2023-40165 is a high-severity flaw (CVSS 7.4) affecting rubygems.org. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.

rubygems.org is the Ruby community's primary gem (library) hosting service. Insufficient input validation allowed malicious actors to replace any uploaded gem version that had a platform, version number, or gem name matching `/-\d/`, permanently replacing the legitimate upload in the canonical gem storage bucket, and triggering an immediate CDN purge so that the malicious gem would be served immediately. The maintainers have checked all gems matc

Why this priority

High severity

A fixed release or distro patch exists.

Risk facts

CVSS score	7.4 (High)
Attack vector	Network (remote)
Attack complexity	Low
Privileges needed	None
User interaction	Required
EPSS exploit chance	0.5% (top 60%)
CISA exploited list	No
Weakness	CWE-20
Published	2023-08-17
Last modified	2026-06-17

Publisher (CNA): GitHub, Inc. · Vendor: rubygems

Last updated 2026-06-17 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score

Am I affected?

Timeline

2023-08-17 18:15 UTCPublished CVE record published
2026-06-17 06:16 UTCUpdated Record last modified

rubygems rubygems.org UPGRADE

Affected: < 2023-08-14

Fixed in: 2023-08-14

Safe to downgrade to: no unaffected older release

1. Check installed version

apt-cache policy rubygems.org || rpm -q rubygems.org || rubygems.org --version

2. UPGRADE to 2023-08-14 (Debian / Ubuntu)

sudo apt update && sudo apt install --only-upgrade rubygems.org

2. UPGRADE (RHEL / Amazon Linux / Fedora)

sudo dnf upgrade rubygems.org

Note

Distros often backport fixes without changing the version number. Confirm with the distro advisory or changelog.

Verify at the official source NVD · CVE Program · Report a problem with this page
Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.

Quick answers

How do I fix CVE-2023-40165?

rubygems.org: upgrade to 2023-08-14. Exact commands for each OS are on this page.

Is CVE-2023-40165 being exploited?

CVE-2023-40165 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.

What does CVE-2023-40165 affect?

CVE-2023-40165 affects rubygems.org. Severity is high (CVSS 7.4). rubygems.org is the Ruby community's primary gem (library) hosting service. Insufficient input validation allowed malicious actors to replace any uploaded gem version that had a platform, version number, or gem name matching `/-\d/`, perman

How urgent is CVE-2023-40165?

Priority 36/100. High severity

Software pages

Ruby vulnerabilities

Related CVEs

CVE-2024-21654 MEDIUM 4.8 UPGRADE Rubygems.org is the Ruby community's gem hosting service

References

← Back to latest CVEs