Vulnerabilities
Misconfiguration
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CVE Vulnerabilities

CVE-2021-33621

Improper Neutralization of Special Elements in Output Used by a Downstream Component ('Injection')

Published: Nov 18, 2022 | Modified: Nov 04, 2025
CVSS 3.x
8.8
HIGH
Source:
NVD
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
CVSS 2.x
RedHat/V2
RedHat/V3
8.8 MODERATE
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Ubuntu
MEDIUM
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Additional information
NVDhttps://nvd.nist.gov/vuln/detail/CVE-2021-33621
CWEhttps://cwe.mitre.org/data/definitions/74.html

The cgi gem before 0.1.0.2, 0.2.x before 0.2.2, and 0.3.x before 0.3.5 for Ruby allows HTTP response splitting. This is relevant to applications that use untrusted user input either to generate an HTTP response or to create a CGI::Cookie object.

Weakness

The product constructs all or part of a command, data structure, or record using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify how it is parsed or interpreted when it is sent to a downstream component.

Affected Software

NameVendorStart VersionEnd Version
CgiRuby-lang*0.1.0.2 (excluding)
CgiRuby-lang0.2.0 (including)0.2.2 (excluding)
CgiRuby-lang0.3.0 (including)0.3.5 (excluding)
Red Hat Enterprise Linux 8RedHatruby:2.7-8080020230427102918.63b34585*
Red Hat Enterprise Linux 8RedHatruby:2.5-8090020230627084142.b46abd14*
Red Hat Enterprise Linux 8RedHatruby:3.1-8090020240311122605.a75119d5*
Red Hat Enterprise Linux 8RedHatruby:3.0-8100020240522072634.489197e6*
Red Hat Enterprise Linux 9RedHatruby:3.1-9030020240320163942.9*
Red Hat Enterprise Linux 9RedHatruby-0:3.0.7-162.el9_4*
Red Hat Enterprise Linux 9.2 Extended Update SupportRedHatruby-0:3.0.4-161.el9_2.1*
Red Hat Software Collections for Red Hat Enterprise Linux 7RedHatrh-ruby27-ruby-0:2.7.8-132.el7*
JrubyUbuntubionic*
JrubyUbuntufocal*
JrubyUbuntulunar*
JrubyUbuntumantic*
JrubyUbuntuoracular*
JrubyUbuntuplucky*
JrubyUbuntutrusty*
JrubyUbuntutrusty/esm*
JrubyUbuntuxenial*
Ruby1.9.1Ubuntutrusty*
Ruby2.0Ubuntutrusty*
Ruby2.3Ubuntuesm-infra/xenial*
Ruby2.3Ubuntuupstream*
Ruby2.3Ubuntuxenial*
Ruby2.5Ubuntubionic*
Ruby2.5Ubuntuesm-infra/bionic*
Ruby2.7Ubuntuesm-infra/focal*
Ruby2.7Ubuntufocal*
Ruby3.0Ubuntujammy*
Ruby3.0Ubuntukinetic*
Ruby3.1Ubuntukinetic*
Ruby3.1Ubuntuupstream*

Potential Mitigations

References

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