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CVE-2022-30122

HIGH

Denial of Service Vulnerability in Rack Multipart Parsing

Published May 27, 2022Updated February 18, 2024Source: osv

Summary

There is a possible denial of service vulnerability in the multipart parsing component of Rack. This vulnerability has been assigned the CVE identifier CVE-2022-30122. Versions Affected: >= 1.2 Not affected: < 1.2 Fixed Versions: 2.0.9.1, 2.1.4.1, 2.2.3.1 ## Impact Carefully crafted multipart POST requests can cause Rack's multipart parser to take much longer than expected, leading to a possible denial of service vulnerability. Impacted code will use Rack's multipart parser to parse multipart posts. This includes directly using the multipart parser like this: ``` params = Rack::Multipart.parse_multipart(env) ``` But it also includes reading POST data from a Rack request object like this: ``` p request.POST # read POST data p request.params # reads both query params and POST data ``` All users running an affected release should either upgrade or use one of the workarounds immediately. ## Workarounds There are no feasible workarounds for this issue.

Remediation

Upgrade to the fixed version using your package manager.

Bundler
Update rack to 2.2.3.1 or later
gem install rack -v 2.2.3.1
Bundler
Update rack to 2.1.4.1 or later
gem install rack -v 2.1.4.1
Bundler
Update rack to 2.0.9.1 or later
gem install rack -v 2.0.9.1

After upgrading, run your dependency scanner again to confirm the vulnerability is resolved.

Affected Packages (3)

PackageEcosystemAffectedFixed In
rack
rubygems
2.2.0, 2.2.1, 2.2.2, 2.2.32.2.3.1
rack
rubygems
2.1.0, 2.1.1, 2.1.2, 2.1.3 (+1 more)2.1.4.1
rack
rubygems
1.2.0, 1.2.1, 1.2.2, 1.2.3 (+61 more)2.0.9.1

Vulnerability Classification

Common Weakness Enumeration (CWE) identifiers for this vulnerability type.

CVSS Score Breakdown

What the CVSS (Common Vulnerability Scoring System) 7.5 score means for each attack dimension.

Attack Vector
Network
Attack Complexity
Low
Privileges Required
None
User Interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
None
Availability
High

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Frequently Asked Questions

What is CVE-2022-30122?
Denial of Service Vulnerability in Rack Multipart Parsing This vulnerability has been assigned a severity rating of HIGH (CVSS score: 7.5/10).
How do I check if my project is affected by CVE-2022-30122?
CVE-2022-30122 affects rack. Use GeekWala's free vulnerability scanner to check your dependencies against CVE-2022-30122 and 200,000+ other known vulnerabilities.

Severity & Exploitability

CVSS Score
7.5

High exploitability or significant impact. Prioritize remediation within days.

Also Known As

GHSA-hxqx-xwvh-44m2

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