CVE-2021-33621
HIGH
8.8
CVSS Score
Published: November 18, 2022 at 12:00 AM UTC
Updated: June 17, 2026 at 03:54 AM UTC
3 products affected across 2 vendorsFedoraRubyCgi
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Severity
HIGH8.8
Exploit prediction
EPSS 2%
Description
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.
Affected
Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.
Cgi· Ruby Langrubygems
95%v < 0.1.0.20.2.0 ≤ v < 0.2.20.3.0 ≤ v < 0.3.5
Affected range stops below 0.1.0.2, so it looks safe — our inference, not a vendor statement
Affected range stops below 0.2.2, so it looks safe — our inference, not a vendor statement
Affected range stops below 0.3.5, so it looks safe — our inference, not a vendor statement
Ruby· Ruby Langrubygems
95%2.7.0 ≤ v < 2.7.73.0.0 ≤ v < 3.0.53.1.0 ≤ v < 3.1.3
Affected range stops below 2.7.7, so it looks safe — our inference, not a vendor statement
Affected range stops below 3.0.5, so it looks safe — our inference, not a vendor statement
Affected range stops below 3.1.3, so it looks safe — our inference, not a vendor statement
Remediation
No guide yetNo remediation guidance has been written for this CVE yet. What the record does show:
Patch and advisory references
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/DQR7LWED6VAPD5ATYOBZIGJQPCUBRJBX/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/THVTYHHEOVLQFCFHWURZYO7PVUPBHRZD/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/YACE6ORF2QBXXBK2V2CM36D7TZMEJVAS/
- https://security.gentoo.org/glsa/202401-27
References (8)
Third Party Advisory
Source: [email protected]
https://security.netapp.com/advisory/ntap-20221228-0004/ExploitThird Party Advisory
Source: [email protected]
https://www.ruby-lang.org/en/news/2022/11/22/http-response-splitting-in-cgi-cve-2021-33621/Source: af854a3a-2127-422b-91ae-364da2661108
https://lists.debian.org/debian-lts-announce/2024/09/msg00000.htmlCVSS
- Attack Vector
- NETWORK
- Complexity
- LOW
- Privileges
- LOW
- User Interaction
- NONE
- Scope
- UNCHANGED
- Confidentiality
- HIGH
- Integrity
- HIGH
- Availability
- HIGH
Vector?
Quick Info
StatusMODIFIED
CWE
CWE-74
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