How severe is CVE-2020-8163?

CVE-2020-8163 has a CVSS score of 8.8/10, rated HIGH. Immediate patching is strongly recommended.

Which packages are affected by CVE-2020-8163?

CVE-2020-8163 affects the following packages: actionview (RubyGems). Ecosystems affected: RubyGems.

How do I fix CVE-2020-8163?

Update actionview to version 4.2.11.3 or later. Run your dependency manager's update command and verify no transitive dependencies pin the vulnerable version. Use O3 Security's SCA scanner to confirm the fix is applied across your entire dependency tree.

Is CVE-2020-8163 actively exploited in the wild?

Yes. There are 6 known exploit references for CVE-2020-8163, including 1 documented proof-of-concept exploit on Exploit-DB and 3 in-the-wild exploitations observed on GitHub and other sources. Treat this as actively exploitable and prioritize patching immediately. All exploit code should only be run in an isolated sandbox environment for research or authorized testing — never against production systems without explicit written authorization.

What is the EPSS score for CVE-2020-8163?

CVE-2020-8163 has an EPSS (Exploit Prediction Scoring System) score of 91.1%, placing it in the 100th percentile of all CVEs. EPSS is maintained by FIRST.org and estimates the probability that a vulnerability will be exploited in the wild within the next 30 days. A score above 50% indicates significantly elevated exploitation risk — immediate patching is strongly recommended.

What type of vulnerability is CVE-2020-8163?

CVE-2020-8163 is classified as Code Injection (CWE-94). This weakness type describe the underlying flaw category, which helps determine the potential impact and the right class of mitigation. This is a high-impact weakness class that often enables remote code execution or data exposure.

Is there exploit tooling available for CVE-2020-8163?

A Nuclei detection template exists for CVE-2020-8163, meaning automated scanners can fingerprint it. Public exploit tooling significantly increases real-world risk — prioritize patching and ensure detection coverage. Exploit tooling should only ever be used in isolated, authorized testing environments.

When was CVE-2020-8163 published, and has it been updated?

CVE-2020-8163 was published on July 2, 2020 and was last updated on April 10, 2026. Advisory data evolves as severity scores, affected ranges, and exploit intelligence are revised — always check the latest version of the advisory before acting.

💎 RubyGems

CVE-2020-8163

HIGH

Remote code execution via user-provided local names in ActionView

Also known asBIT-rails-2020-8163GHSA-cr3x-7m39-c6jq

Published

Jul 2, 2020

Updated

Apr 10, 2026

Affected

1 pkg

Patched

1 / 1

Exploits

6 known

EPSS Exploitation Probability

via FIRST.org ↗

91.1%probability of exploitation in next 30 days

Very High Risk100th percentile0.00%

EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.

Blast Radius

1 pkg affected

💎actionview

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

The is a code injection vulnerability in versions of Rails prior to 5.0.1 that wouldallow an attacker who controlled the locals argument of a render call to perform a RCE.

Affected Packages

1 total 1 fixed

Ecosystem	Package	Vulnerable range	Fix
💎RubyGems	`actionview`	all versions	4.2.11.3

Exploits & PoCs

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

EDB-48716webappsruby

Rails 5.0.1 - Remote Code Execution

by Lucas Amorim · Jul 26, 2020

Exploit-DB Source

Frequently Asked Questions

The is a code injection vulnerability in versions of Rails prior to 5.0.1 that wouldallow an attacker who controlled the `locals` argument of a `render` call to perform a RCE.

O3 Security · Impact-Aware SCA

Is CVE-2020-8163 in your stack?

O3 detects CVE-2020-8163 across RubyGems dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.

Scan my stack How O3 SCA works