CVE-2020-8163

Exp

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.

Published: 2020-07-02 Last update: 2026-06-16 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2020-8163 is rated High Exploit Risk (80.1/100): CVSS High severity, with high exploitation likelihood (EPSS 83.08%, 100th percentile). 2 public exploit reference(s) are indexed (Exploit-DB). Public exploits are available—assess exposure, apply mitigations, and prioritize patching.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Public exploit references (Exploit-DB) for CVE-2020-8163

EDB-ID Source Kind Published Link
48716 exploit_db edb 2020-07-26 Exploit-DB ↗
— nvd_ref exploit_tag Exploit-DB ↗

Exploit prediction scoring system (EPSS) score for CVE-2020-8163

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-06-15 91.07% 83.08% -7.99%
2 2026-04-23 90.93% 91.07% +0.14%
3 2026-03-04 — 90.93% —

Full EPSS history (58 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2020-8163

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
8.8 3.1 HIGH
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:L)
A normal user session is enough; they don’t have to be admin.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 2.8 5.9 [email protected]
6.5 2.0 MEDIUM
AV:N/AC:L/Au:S/C:P/I:P/A:P Click to expand
Access vector (AV:N)
Can be exploited remotely over network reachability.
Access complexity (AC:L)
Exploitation conditions are straightforward and predictable.
Authentication (AU:S)
A single authentication is required.
Confidentiality impact (C:P)
Partial confidentiality impact.
Integrity impact (I:P)
Partial integrity impact.
Availability impact (A:P)
Partial availability impact.
 8.0 6.4 [email protected]

Weakness enumeration for CVE-2020-8163

GitHub Security Advisory for CVE-2020-8163

GHSA-cr3x-7m39-c6jq · Severity: high · Ecosystem: rubygems — Remote code execution via user-provided local names in ActionView

OS Trackers for CVE-2020-8163

vendor priority summary link
debian not yet assigned CVE-2020-8163 not yet assigned priority: Debian including 1 source packages (rails), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 5. https://security-tracker.debian.org/tracker/CVE-2020-8163
redhat high — https://access.redhat.com/security/cve/CVE-2020-8163
suse high — https://www.suse.com/security/cve/CVE-2020-8163/
ubuntu medium CVE-2020-8163 medium priority: Ubuntu including 7 source packages (rails, rails-4.0, …), 119 status rows across 17 suites (bionic, eoan, focal, groovy, hirsute, impish, jammy, kinetic, lunar, mantic, noble, oracular, plucky, questing, trusty, upstream, xenial): DNE 97, needs-triage 13, ignored 9. https://ubuntu.com/security/CVE-2020-8163

Affected software / configurations for CVE-2020-8163

Vendor Product Version Raw CPE
rubyonrails rails < 5.0.1 cpe:2.3:a:rubyonrails:rails:*:*:*:*:*:*:*:*
debian debian_linux 9.0 cpe:2.3:o:debian:debian_linux:9.0:*:*:*:*:*:*:*

References for CVE-2020-8163

cvelogic Threat Intelligence