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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…
Critical9.8EPSS 89.3%
- Published
- Updated
- Reserved
- Assigned by
- hackerone
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.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| NVDNVD · Modified | 3.1 | Critical9.8 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |
- EPSS (exploitation in 30 days)
- 89.3% · top 0.2% of all CVEs (6 Nov 2026)
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The list uses the assigner's score when there is one, then CISA's, then NVD's: Critical 9.8.
Weakness
Affected products
Rails · https://github.com/rails/rails
- affected 5.2.2.1
- affected 6.0.0.beta3
Affected packages
From reviewed advisories of the GitHub Advisory Database.
- RubyGemsrailtiesGHSA-m42h-mh85-4qgc (opens in a new tab)
References (5)
- https://weblog.rubyonrails.org/2019/3/13/Rails-4-2-5-1-5-1-6-2-have-been-released/ (opens in a new tab)x_refsource_CONFIRMx_transferred
- https://groups.google.com/forum/#%21topic/rubyonrails-security/IsQKvDqZdKw (opens in a new tab)x_refsource_CONFIRMx_transferred
- http://packetstormsecurity.com/files/152704/Ruby-On-Rails-DoubleTap-Development-Mode-secret_key_base-Remote-Code-Execution.html (opens in a new tab)x_refsource_MISCx_transferred
- 46785 (opens in a new tab)exploitx_refsource_EXPLOIT-DBx_transferred
- FEDORA-2019-1cfe24db5c (opens in a new tab)vendor-advisoryx_refsource_FEDORAx_transferred
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisory GHSA-m42h-mh85-4qgc (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://trackcve.app/cve/CVE-2019-5420)Record last updated .