CVE-2025-27219
highpriority · track · 30EPSS 0.008 · 58 %ileDEEURUUSEPSS · scored 2026-10-28
In the CGI gem before 0.4.2 for Ruby, the CGI::Cookie.parse method in the CGI library contains a potential Denial of Service (DoS) vulnerability. The method does not impose any limit on the length of the raw cookie value it processes. This oversight can lead to excessive resource consumption when parsing extremely large cookies.
cvss
Technical severity, 0–10. One row per scoring source.
base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 5.8–7.5
ssvc
A stakeholder decision — act, attend, or track — from exploitation and impact.
weaknesses
The CWE weakness classes this flaw belongs to.
affected products (24)
Products and version ranges known to be affected.
advisories (3)
Vendor and ecosystem advisories describing this.
- WID-SEC-W-2025-0438Ruby (CGI und URI gem): Mehrere SchwachstellenDeutsch2025-02-25csaf · cert_bundDE
Ein entfernter, anonymer Angreifer kann mehrere Schwachstellen in Ruby ausnutzen, um einen Denial-of-Service-Zustand zu erzeugen und vertrauliche Informationen preiszugeben.
- WID-SEC-W-2025-1439Dell Secure Connect Gateway: Mehrere Schwachstellen ermöglichen nicht spezifizierten AngriffDeutsch2025-06-30csaf · cert_bundDE
Ein Angreifer kann mehrere Schwachstellen in Dell Secure Connect Gateway ausnutzen, um einen nicht näher spezifizierten Angriff durchzuführen.
- GHSA-gh9q-2xrm-x6qvCGI has Denial of Service (DoS) potential in Cookie.parse2025-03-03ghsa · osvUS
There is a possibility for DoS by in the cgi gem. This vulnerability has been assigned the CVE identifier CVE-2025-27219. We recommend upgrading the cgi gem. ## Details CGI::Cookie.parse took super-linear time to parse a cookie string in some cases. Feeding a maliciously crafted cookie string into the method could lead to a Denial of Service. Please update CGI gem to version 0.3.5.1, 0.3.7, 0.4.2 or later. ## Affected versions cgi gem versions <= 0.3.5, 0.3.6, 0.4.0 and 0.4.1. ## Credits Thanks to lio346 for discovering this issue. Also thanks to mame for fixing this vulnerability.
also known as (4)
Other names and identifiers for this entity.
sources
Which sources assert this record, and when.
references (10)
External citations — patches, advisories, analysis.
- https://github.com/ruby/cgi/releases/tag/v0.4.2Patchcnnvd
- https://github.com/rubysec/ruby-advisory-db/blob/master/gems/cgi/CVE-2025-27219.ymlcnnvd
- https://hackerone.com/reports/2936778cnnvd
- https://nvd.nist.gov/vuln/detail/CVE-2025-27219cnnvd
- https://vigilance.fr/vulnerability/Ruby-CGI-URI-three-vulnerabilities-dated-26-02-2025-46457cnnvd
- https://github.com/rubysec/ruby-advisory-db/blob/master/gems/cgi/CVE-2025-27219.ymlenisa_euvd
- https://hackerone.com/reports/2936778enisa_euvd
- https://github.com/rubysec/ruby-advisory-db/blob/master/gems/cgi/CVE-2025-27219.ymlThird Party Advisorynvd
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