Ruby cgi.rb response splitting

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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7.2$0-$5k0.00

Summaryinfo

A vulnerability marked as critical has been reported in Ruby. The affected element is an unknown function of the file cgi.rb. The manipulation leads to response splitting. This vulnerability is listed as CVE-2021-33621. The attack may be initiated remotely. In addition, an exploit is available. It is suggested to upgrade the affected component.

Detailsinfo

A vulnerability was found in Ruby (Programming Language Software) (the affected version is unknown). It has been rated as critical. This issue affects an unknown code of the file cgi.rb. The manipulation with an unknown input leads to a response splitting vulnerability. Using CWE to declare the problem leads to CWE-443. This weakness can be found at CWE-113. Impacted is confidentiality, integrity, and availability. The summary by CVE is:

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.

The weakness was presented 11/23/2022. The advisory is shared at ruby-lang.org. The identification of this vulnerability is CVE-2021-33621 since 05/28/2021. Technical details as well as a public exploit are known.

The exploit is available at ruby-lang.org. It is declared as proof-of-concept. The vulnerability scanner Nessus provides a plugin with the ID 214476 (Debian dla-3450 : libruby2.5 - security update), which helps to determine the existence of the flaw in a target environment.

Upgrading eliminates this vulnerability.

The vulnerability is also documented in the vulnerability database at Tenable (214476). If you want to get the best quality for vulnerability data then you always have to consider VulDB.

Productinfo

Type

Name

License

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 7.6
VulDB Meta Temp Score: 7.2

VulDB Base Score: 6.3
VulDB Temp Score: 5.7
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 8.8
NVD Vector: 🔍

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔍
VulDB Temp Score: 🔍
VulDB Reliability: 🔍

Exploitinginfo

Class: Response splitting
CWE: CWE-443 / CWE-436
CAPEC: 🔍
ATT&CK: 🔍

Physical: No
Local: No
Remote: Yes

Availability: 🔍
Access: Public
Status: Proof-of-Concept
Download: 🔍

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Nessus ID: 214476
Nessus Name: Debian dla-3450 : libruby2.5 - security update

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔍

Timelineinfo

05/28/2021 🔍
11/23/2022 +544 days 🔍
11/23/2022 +0 days 🔍
11/05/2025 +1078 days 🔍

Sourcesinfo

Advisory: FEDORA-2022-b9b710f199
Status: Confirmed

CVE: CVE-2021-33621 (🔍)
GCVE (CVE): GCVE-0-2021-33621
GCVE (VulDB): GCVE-100-214253
scip Labs: https://www.scip.ch/en/?labs.20161013

Entryinfo

Created: 11/23/2022 13:21
Updated: 11/05/2025 13:08
Changes: 11/23/2022 13:21 (49), 12/22/2022 14:13 (1), 01/23/2025 04:38 (16), 11/05/2025 13:08 (1)
Complete: 🔍
Cache ID: 216::103

If you want to get the best quality for vulnerability data then you always have to consider VulDB.

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