Critical severity · published Mar 27, 2019
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
9.8
CVSS
89.3%
EPSS
No
On KEV
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.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
High
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)89.3% · higher than 100% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
DL
Debian Linux · Debian
8.0 · source: NVD
FE
Fedora · Fedoraproject
30 · source: NVD
RA
Rails · Rubyonrails
before 5.2.2.1; 6.0.0; 6.0.0 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2019-5420
CVE.org
https://www.cve.org/CVERecord?id=CVE-2019-5420
Exploit
http://packetstormsecurity.com/files/152704/Ruby-On-Rails-DoubleTap-Development-Mode-secret_key_base-Remote-Code-Execution.html
groups.google.com
https://groups.google.com/forum/#%21topic/rubyonrails-security/IsQKvDqZdKw
lists.fedoraproject.org
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/Y43636TH4D6T46IC6N2RQVJTRFJAAYGA/
Patch
https://weblog.rubyonrails.org/2019/3/13/Rails-4-2-5-1-5-1-6-2-have-been-released/
Exploit
https://www.exploit-db.com/exploits/46785/
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