CVE-2020-36327

Name: CVE-2020-36327
Creator: NVD / NIST
Published: 2021-04-29T03:15:08.71+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

HIGHCVSS 8.8/10EPSS 6.31%

Last modified Jun 17, 2026

CVE-2020-36327 is a high-severity vulnerability rated 8.8/10 on the CVSS scale. Bundler 1.16.0 through 2.2.9 and 2.2.11 through 2.2.16 sometimes chooses a dependency source based on the highest gem version number, which means that a rogue gem found at a public source may be chosen, even if the intended choice was a private gem that is a dependency of another private gem that is explicitly depended on by the application. NOTE: it is not correct to use CVE-2021-24105 for every "Dependency Confusion" issue in every product.. EPSS estimates a 6.31% chance of exploitation in the next 30 days.

Description

Bundler 1.16.0 through 2.2.9 and 2.2.11 through 2.2.16 sometimes chooses a dependency source based on the highest gem version number, which means that a rogue gem found at a public source may be chosen, even if the intended choice was a private gem that is a dependency of another private gem that is explicitly depended on by the application. NOTE: it is not correct to use CVE-2021-24105 for every "Dependency Confusion" issue in every product.

Metrics

CVSS 3.1

8.8/10

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

EPSS Probability

6.31%

92.7th percentile

Probability of exploitation in the next 30 days. Learn more

Affected Software

Vendor	Product	Versions
Bundler	Bundler	>= 1.16.0, < 2.2.10
Bundler	Bundler	>= 2.2.11, <= 2.2.16
Fedoraproject	Fedora	34
Microsoft	Package Manager Configurations	All versions

References

https://bundler.io/blog/2021/02/15/a-more-secure-bundler-we-fixed-our-source-priorities.htmlVendor Advisory
https://github.com/rubygems/rubygems/issues/3982Exploit, Issue Tracking, Third Party Advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/MWXHK5UUHVSHF7HTHMX6JY3WXDVNIHSL/
https://mensfeld.pl/2021/02/rubygems-dependency-confusion-attack-side-of-things/Third Party Advisory
https://msrc.microsoft.com/update-guide/en-US/vulnerability/CVE-2021-24105Patch, Vendor Advisory
https://www.zofrex.com/blog/2021/04/29/bundler-still-vulnerable-dependency-confusion-cve-2020-36327/Exploit, Third Party Advisory
https://bundler.io/blog/2021/02/15/a-more-secure-bundler-we-fixed-our-source-priorities.htmlVendor Advisory
https://github.com/rubygems/rubygems/issues/3982Exploit, Issue Tracking, Third Party Advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/MWXHK5UUHVSHF7HTHMX6JY3WXDVNIHSL/
https://mensfeld.pl/2021/02/rubygems-dependency-confusion-attack-side-of-things/Third Party Advisory
https://msrc.microsoft.com/update-guide/en-US/vulnerability/CVE-2021-24105Patch, Vendor Advisory
https://www.zofrex.com/blog/2021/04/29/bundler-still-vulnerable-dependency-confusion-cve-2020-36327/Exploit, Third Party Advisory

Timeline

Published: Apr 29, 2021
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2020-36327?

How severe is CVE-2020-36327?

CVE-2020-36327 has a CVSS score of 8.8/10 (HIGH severity). The EPSS model estimates a 6.31% probability of exploitation in the next 30 days.

How do I fix CVE-2020-36327?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2020-36327?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST