# CVE-2019-5420

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.

- Page: https://www.vulneraibility.com/cve/CVE-2019-5420
- CVSS: 9.8
- Known exploited: not in CISA KEV as of our last sync
- EPSS: 89.33% (percentile 99.8)
- Public exploit code: 1 on Exploit-DB · 1 Metasploit module · 12 GitHub proofs of concept (first 2019-03-21)
- Weakness: CWE-77
- Published: 2019-03-27

## Affected versions

- Rails https://github.com/rails/rails: affected 5.2.2.1; 6.0.0.beta3

A version outside these ranges is not a statement that it is unaffected.

## References

- [other] https://weblog.rubyonrails.org/2019/3/13/Rails-4-2-5-1-5-1-6-2-have-been-released/
- [other] https://groups.google.com/forum/#%21topic/rubyonrails-security/IsQKvDqZdKw
- [other] http://packetstormsecurity.com/files/152704/Ruby-On-Rails-DoubleTap-Development-Mode-secret_key_base-Remote-Code-Execution.html
- [exploit] https://www.exploit-db.com/exploits/46785/
- [advisory] https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/Y43636TH4D6T46IC6N2RQVJTRFJAAYGA/

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Summary, impact and action are written by the vulneraibility.com AI analysis pipeline from the CVE record, NVD, CISA and FIRST data; verify against the references.