CVE-2020-36327
CVE-2020-36327 is a high-severity vulnerability in Bundler with a CVSS 3.x base score of 8.8. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low.
Key facts
- Severity: High (CVSS 3.x base score 8.8)
- CVSS v2: 9.3
- EPSS exploit prediction: 6% (93rd percentile)
- Actively exploited: Not listed in CISA KEV
- Affected product: Bundler
- Published:
- Last modified:
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.
Frequently asked questions
- What is CVE-2020-36327?
- 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.
- How severe is CVE-2020-36327?
- CVE-2020-36327 has a CVSS 3.x base score of 8.8, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is high, integrity high, and availability high.
- Is CVE-2020-36327 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 6% (93rd percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2020-36327?
- CVE-2020-36327 primarily affects Bundler. In total, 3 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
- How do I fix CVE-2020-36327?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
- When was CVE-2020-36327 published?
- CVE-2020-36327 was published on 2021-04-29 and last updated on 2026-06-17.
References
- https://bundler.io/blog/2021/02/15/a-more-secure-bundler-we-fixed-our-source-priorities.html
- https://github.com/rubygems/rubygems/issues/3982
- 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/
- https://msrc.microsoft.com/update-guide/en-US/vulnerability/CVE-2021-24105
- https://www.zofrex.com/blog/2021/04/29/bundler-still-vulnerable-dependency-confusion-cve-2020-36327/
Affected products (3)
- cpe:2.3:a:bundler:bundler:*:*:*:*:*:ruby:*:*
- cpe:2.3:o:fedoraproject:fedora:34:*:*:*:*:*:*:*
- cpe:2.3:a:microsoft:package_manager_configurations:-:*:*:*:*:*:*:*
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