CVE-2019-5420

critical

Description

A remote code execution vulnerability in development mode Rails <5.2.2.1, <6.0.0.beta3 can allow an attacker to guess the automatically generated development mode secret token. This secret token can be used in combination with other Rails internals to escalate to a remote code execution exploit.

References

https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/Y43636TH4D6T46IC6N2RQVJTRFJAAYGA/

https://www.exploit-db.com/exploits/46785/

https://github.com/trickstersec/CVE-2019-5420

https://github.com/cved-sources/cve-2019-5420

https://github.com/mpgn/Rails-doubletap-RCE

https://github.com/knqyf263/CVE-2019-5420

https://github.com/advisories/GHSA-m42h-mh85-4qgc

https://weblog.rubyonrails.org/2019/3/13/Rails-4-2-5-1-5-1-6-2-have-been-released/

https://groups.google.com/forum/#%21topic/rubyonrails-security/IsQKvDqZdKw

http://packetstormsecurity.com/files/152704/Ruby-On-Rails-DoubleTap-Development-Mode-secret_key_base-Remote-Code-Execution.html

Details

Source: Mitre, NVD

Published: 2019-03-27

Updated: 2026-06-17

Risk Information

CVSS v2

Base Score: 7.5

Vector: CVSS2#AV:N/AC:L/Au:N/C:P/I:P/A:P

Severity: High

CVSS v3

Base Score: 9.8

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

Severity: Critical

EPSS

EPSS: 0.92144