CVE-2020-8159
CVE-2020-8159 is a critical-severity vulnerability in Rubyonrails Actionpack Page-caching with a CVSS 3.x base score of 9.8. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-22.
Key facts
- Severity: Critical (CVSS 3.x base score 9.8)
- CVSS v2: 7.5
- EPSS exploit prediction: 5% (92nd percentile)
- Actively exploited: Not listed in CISA KEV
- Weakness: CWE-22
- Affected product: Rubyonrails Actionpack Page-caching
- Published:
- Last modified:
Description
There is a vulnerability in actionpack_page-caching gem < v1.2.1 that allows an attacker to write arbitrary files to a web server, potentially resulting in remote code execution if the attacker can write unescaped ERB to a view.
Frequently asked questions
- What is CVE-2020-8159?
- There is a vulnerability in actionpack_page-caching gem < v1.2.1 that allows an attacker to write arbitrary files to a web server, potentially resulting in remote code execution if the attacker can write unescaped ERB to a view.
- How severe is CVE-2020-8159?
- CVE-2020-8159 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
- Is CVE-2020-8159 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 5% (92nd percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2020-8159?
- CVE-2020-8159 primarily affects Rubyonrails Actionpack Page-caching. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
- How do I fix CVE-2020-8159?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
- When was CVE-2020-8159 published?
- CVE-2020-8159 was published on 2020-05-12 and last updated on 2026-06-17.
References
- https://groups.google.com/forum/#%21topic/rubyonrails-security/CFRVkEytdP8
- https://lists.debian.org/debian-lts-announce/2021/07/msg00019.html
Affected products (2)
- cpe:2.3:a:rubyonrails:actionpack_page-caching:*:*:*:*:*:ruby:*:*
- cpe:2.3:o:debian:debian_linux:9.0:*:*:*:*:*:*:*
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