High severity · published Mar 4, 2025
CVE-2025-27220
In the CGI gem before 0.4.2 for Ruby, a Regular Expression Denial of Service (ReDoS) vulnerability exists in the Util#escapeElement method
7.5
CVSS
0.8%
EPSS
No
On KEV
Description
In the CGI gem before 0.4.2 for Ruby, a Regular Expression Denial of Service (ReDoS) vulnerability exists in the Util#escapeElement method.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
None
Integrity
None
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.8% · higher than 55% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
CG
Cgi · Ruby-lang
before 0.3.5.1; 0.4.0 before 0.4.2; 0.3.6 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2025-27220
CVE.org
https://www.cve.org/CVERecord?id=CVE-2025-27220
Third Party Advisory
https://github.com/rubysec/ruby-advisory-db/blob/master/gems/cgi/CVE-2025-27220.yml
Permissions Required
https://hackerone.com/reports/2890322
lists.debian.org
https://lists.debian.org/debian-lts-announce/2025/03/msg00008.html
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