high
7.5
CWE
565
Advisory Published
CVE Published
Advisory Published
Updated

CVE-2021-41819

First published: Wed Nov 24 2021(Updated: )

A flaw was found in Ruby. RubyGems cgi gem could allow a remote attacker to conduct spoofing attacks caused by the mishandling of security prefixes in cookie names in the CGI::Cookie.parse function. By sending a specially-crafted request, an attacker could perform cookie prefix spoofing attacks.

Credit: cve@mitre.org cve@mitre.org cve@mitre.org

Affected SoftwareAffected VersionHow to fix
rubygems/cgi<0.1.0.1
0.1.0.1
rubygems/cgi=0.2.0
0.2.1
rubygems/cgi=0.3.0
0.3.1
redhat/rh-ruby26-ruby<0:2.6.9-120.el7
0:2.6.9-120.el7
redhat/rh-ruby30-ruby<0:3.0.4-149.el7
0:3.0.4-149.el7
redhat/rh-ruby27-ruby<0:2.7.6-131.el7
0:2.7.6-131.el7
Ruby-lang Cgi=0.1.0
Ruby-lang Cgi=0.2.0
Ruby-lang Cgi=0.3.0
Ruby-lang Ruby<=2.6.8
Ruby-lang Ruby>=2.7.0<2.7.5
Ruby-lang Ruby>=3.0.0<3.0.3
Redhat Software Collections
Redhat Enterprise Linux=8.0
Debian Debian Linux=9.0
Debian Debian Linux=10.0
Debian Debian Linux=11.0
SUSE Linux Enterprise=11.0-sp1
SUSE Linux Enterprise=12.0
SUSE Linux Enterprise=15.0
openSUSE Factory
openSUSE Leap=15.2
Fedoraproject Fedora=34
Fedoraproject Fedora=35
redhat/cgi<0.3.1
0.3.1
redhat/cgi<0.2.1
0.2.1
redhat/cgi<0.1.1
0.1.1
redhat/ruby<3.0.3
3.0.3
redhat/ruby<2.7.5
2.7.5
redhat/ruby<2.6.9
2.6.9
=0.1.0
=0.2.0
=0.3.0
<=2.6.8
>=2.7.0<2.7.5
>=3.0.0<3.0.3
=8.0
=9.0
=10.0
=11.0
=11.0-sp1
=12.0
=15.0
=15.2
=34
=35

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Parent vulnerabilities

(Appears in the following advisories)

Frequently Asked Questions

  • What is CVE-2021-41819?

    CVE-2021-41819 is a vulnerability in Ruby that allows remote attackers to conduct cookie prefix spoofing attacks.

  • How does CVE-2021-41819 affect RubyGems CGI gem?

    CVE-2021-41819 affects the CGI gem in RubyGems, specifically the CGI::Cookie.parse function.

  • What is the severity of CVE-2021-41819?

    CVE-2021-41819 has a severity rating of high.

  • How can an attacker exploit CVE-2021-41819?

    An attacker can exploit CVE-2021-41819 by sending a specially-crafted request to perform cookie prefix spoofing attacks.

  • How can I fix CVE-2021-41819?

    To fix CVE-2021-41819, update to the latest version of RubyGems CGI gem that includes the necessary security patches.

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