CGI::Cookie.parse in Ruby through 2.6.8 mishandles security prefixes in cookie names. This also affects the CGI gem through 0.3.0 for Ruby.

No CVSS v4.0

Attack Vector Network

Attack Complexity Low

Privileges Required None

Scope Unchanged

Confidentiality Impact None

Integrity Impact High

Availability Impact None

User Interaction None

No CVSS v3.0

Access Vector Network

Access Complexity Low

Authentication None

Confidentiality Impact None

Integrity Impact Partial

Availability Impact None

This CVE is not in the KEV list.

The EPSS score is 0.00755.

Exploitation none

Automatable no

Technical Impact partial

Default status is the baseline for the product, each version can override it (e.g. patched versions marked unaffected).

Vendor Product Default status Versions
n/a n/a affected
Version Status Constraints
n/a affected
—

Configuration 1 [-]

OR cpe:2.3:a:ruby-lang:cgi:0.1.0:*:*:*:*:ruby:*:*
cpe:2.3:a:ruby-lang:cgi:0.2.0:*:*:*:*:ruby:*:*
cpe:2.3:a:ruby-lang:cgi:0.3.0:*:*:*:*:ruby:*:*
cpe:2.3:a:ruby-lang:ruby:*:*:*:*:*:*:*:*
cpe:2.3:a:ruby-lang:ruby:*:*:*:*:*:*:*:*
cpe:2.3:a:ruby-lang:ruby:*:*:*:*:*:*:*:*

Configuration 2 [-]

OR cpe:2.3:a:redhat:software_collections:-:*:*:*:*:*:*:*
cpe:2.3:o:redhat:enterprise_linux:8.0:*:*:*:*:*:*:*

Configuration 3 [-]

OR cpe:2.3:o:debian:debian_linux:9.0:*:*:*:*:*:*:*
cpe:2.3:o:debian:debian_linux:10.0:*:*:*:*:*:*:*
cpe:2.3:o:debian:debian_linux:11.0:*:*:*:*:*:*:*

Configuration 4 [-]

OR cpe:2.3:o:suse:linux_enterprise:11.0:sp1:*:*:*:*:*:*
cpe:2.3:o:suse:linux_enterprise:12.0:*:*:*:*:*:*:*
cpe:2.3:o:suse:linux_enterprise:15.0:*:*:*:*:*:*:*

Configuration 5 [-]

OR cpe:2.3:a:opensuse:factory:-:*:*:*:*:*:*:*
cpe:2.3:o:opensuse:leap:15.2:*:*:*:*:*:*:*

Configuration 6 [-]

OR cpe:2.3:o:fedoraproject:fedora:34:*:*:*:*:*:*:*
cpe:2.3:o:fedoraproject:fedora:35:*:*:*:*:*:*:*
Package CPE Advisory Released Date
Red Hat Enterprise Linux 8
ruby:2.6-8050020211215144356.c5368500 cpe:/a:redhat:enterprise_linux:8 RHSA-2022:0543 2022-02-16T00:00:00Z
ruby:2.5-8060020220715152618.ad008a3a cpe:/a:redhat:enterprise_linux:8 RHSA-2022:5779 2022-08-01T00:00:00Z
ruby:2.7-8060020220728151401.ad008a3a cpe:/a:redhat:enterprise_linux:8 RHSA-2022:6447 2022-09-13T00:00:00Z
ruby:3.0-8060020220810162001.ad008a3a cpe:/a:redhat:enterprise_linux:8 RHSA-2022:6450 2022-09-13T00:00:00Z
Red Hat Enterprise Linux 8.1 Update Services for SAP Solutions
ruby:2.6-8010020220201152941.c27ad7f8 cpe:/a:redhat:rhel_e4s:8.1 RHSA-2022:0581 2022-02-21T00:00:00Z
Red Hat Enterprise Linux 8.2 Extended Update Support
ruby:2.6-8020020220201131207.4cda2c84 cpe:/a:redhat:rhel_eus:8.2 RHSA-2022:0582 2022-02-21T00:00:00Z
Red Hat Enterprise Linux 8.4 Extended Update Support
ruby:2.6-8040020220131135901.522a0ee4 cpe:/a:redhat:rhel_eus:8.4 RHSA-2022:0544 2022-02-16T00:00:00Z
Red Hat Software Collections for Red Hat Enterprise Linux 7
rh-ruby26-ruby-0:2.6.9-120.el7 cpe:/a:redhat:rhel_software_collections:3::el7 RHSA-2022:0708 2022-02-28T00:00:00Z
rh-ruby30-ruby-0:3.0.4-149.el7 cpe:/a:redhat:rhel_software_collections:3::el7 RHSA-2022:6855 2022-10-11T00:00:00Z
rh-ruby27-ruby-0:2.7.6-131.el7 cpe:/a:redhat:rhel_software_collections:3::el7 RHSA-2022:6856 2022-10-11T00:00:00Z

No data.

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Tracking

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Advisories
Source ID Title
Debian DLA Debian DLA DLA-2853-1 ruby2.3 security update
Debian DSA Debian DSA DSA-5066-1 ruby2.5 security update
Debian DSA Debian DSA DSA-5067-1 ruby2.7 security update
Github GHSA Github GHSA GHSA-4vf4-qmvg-mh7h Cookie Prefix Spoofing in CGI::Cookie.parse
Ubuntu USN Ubuntu USN USN-5235-1 Ruby vulnerabilities
Fixes

Solution

No solution given by the vendor.

Workaround

No workaround given by the vendor.

References
Link Providers
https://hackerone.com/reports/910552 cve-icon cve-icon
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/IUXQCH6FRKANCVZO2Q7D2SQX33FP3KWN/ cve-icon cve-icon
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/UTOJGS5IEFDK3UOO7IY4OTTFGHGLSWZF/ cve-icon cve-icon
https://nvd.nist.gov/vuln/detail/CVE-2021-41819 cve-icon
https://security.gentoo.org/glsa/202401-27 cve-icon cve-icon
https://security.netapp.com/advisory/ntap-20220121-0003/ cve-icon cve-icon
https://www.cve.org/CVERecord?id=CVE-2021-41819 cve-icon
https://www.ruby-lang.org/en/news/2021/11/24/cookie-prefix-spoofing-in-cgi-cookie-parse-cve-2021-41819/ cve-icon cve-icon
History

Thu, 22 May 2025 15:15:00 +0000

Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}
cve-icon MITRE

Status: PUBLISHED

Assigner: mitre

Published:

Updated: 2025-05-22T15:00:52.998Z

Reserved: 2021-09-29T00:00:00.000Z

Link: CVE-2021-41819

cve-icon Vulnrichment

Updated: 2024-08-04T03:22:24.942Z

cve-icon NVD

Status : Modified

Published: 2022-01-01T06:15:07.293

Modified: 2025-05-22T15:15:54.060

Link: CVE-2021-41819

cve-icon Redhat

Severity : Moderate

Publid Date: 2021-11-24T00:00:00Z

Links: CVE-2021-41819 - Bugzilla

cve-icon OpenCVE Enrichment

No data.

Weaknesses