CVE-2023-27530: Input Validation

Published Mar 8, 2023
·
Updated

A DoS vulnerability exists in Rack <v3.0.4.2, <v2.2.6.3, <v2.1.4.3 and <v2.0.9.3 within in the Multipart MIME parsing code in which could allow an attacker to craft requests that can be abuse to cause multipart parsing to take longer than expected.

Other sources

A flaw was found in rubygem-rack. This issue occurs in the Multipart MIME parsing code in Rack, which limits the number of file parts but does not limit the total number of parts that can be uploaded. Carefully crafted requests can abuse this and cause multipart parsing to take longer than expected, resulting in a denial of service.

There is a possible DoS vulnerability in the Multipart MIME parsing code in Rack. This vulnerability has been assigned the CVE identifier CVE-2023-27530.

Versions Affected: All. Not affected: None Fixed Versions: 3.0.4.2, 2.2.6.3, 2.1.4.3, 2.0.9.3

Impact The Multipart MIME parsing code in Rack limits the number of file parts, but does not limit the total number of parts that can be uploaded. Carefully crafted requests can abuse this and cause multipart parsing to take longer than expected.

All users running an affected release should either upgrade or use one of the workarounds immediately.

Workarounds A proxy can be configured to limit the POST body size which will mitigate this issue.

GitHub

Affected Software

24 affected componentsFixes available
redhat/pcs<0:0.10.15-4.el8_8.1
0:0.10.15-4.el8_8.1
redhat/pcs<0:0.10.8-1.el8_4.4
0:0.10.8-1.el8_4.4
redhat/pcs<0:0.10.12-6.el8_6.4
0:0.10.12-6.el8_6.4
redhat/pcs<0:0.11.4-7.el9_2
0:0.11.4-7.el9_2
redhat/pcs<0:0.11.1-10.el9_0.4
0:0.11.1-10.el9_0.4
redhat/rubygem-rack<3.0.4.2
3.0.4.2
redhat/rubygem-rack<2.2.6.3
2.2.6.3
redhat/rubygem-rack<2.1.4.3
2.1.4.3
redhat/rubygem-rack<2.0.9.3
2.0.9.3
rubygems/rack>=3.0.0<3.0.4.2
3.0.4.2
rubygems/rack>=2.2.0<2.2.6.3
2.2.6.3
rubygems/rack>=2.1.0<2.1.4.3
2.1.4.3
rubygems/rack<2.0.9.3
2.0.9.3
Rack Project Rack Ruby<2.0.9.3
Rack Project Rack Ruby>=2.1.0<2.1.4.3
Rack Project Rack Ruby>=2.2.0<2.2.6.3
Rack Project Rack Ruby>=3.0.0<3.0.4.2
debian/ruby-rack
2.1.4-3+deb11u22.1.4-3+deb11u32.2.6.4-1+deb12u12.2.13-1~deb12u13.1.12-1
Rack Rack Ruby<2.0.9.3
Rack Rack Ruby>=2.1.0<2.1.4.3
Rack Rack Ruby>=2.2.0<2.2.6.3
Rack Rack Ruby>=3.0.0<3.0.4.2
Debian Debian Linux=10.0
Debian Debian Linux=11.0

Event History

Mar 8, 2023
CVE Published
12:00 AM
Advisory Published
via GitHub·05:20 PM
Mar 10, 2023
CVE Published
via MITRE·12:00 AM
Data Sourced
via MITRE·12:00 AM
DescriptionWeakness
Mar 11, 2023
Data Sourced
08:12 PM
SeverityAffected Software
Jun 19, 2024
Data Sourced
via Launchpad·12:12 PM
Description
Sep 27, 2024
Data Sourced
via Ubuntu·12:25 PM
RemedyDescriptionSeverityAffected Software
Mar 26, 2025
Data Sourced
via Debian·12:56 PM
DescriptionAffected Software

Parent advisories

This vulnerability appears in the following advisories.

Frequently Asked Questions

1

What is the vulnerability ID?

The vulnerability ID is CVE-2023-27530.

2

What is the severity of CVE-2023-27530?

The severity of CVE-2023-27530 is high.

3

What software is affected by CVE-2023-27530?

The affected software is rubygem-rack versions <3.0.4.2, <2.2.6.3, <2.1.4.3, and <2.0.9.3.

4

How can I exploit CVE-2023-27530?

Carefully crafted requests can abuse this vulnerability and cause multipart parsing to take longer than expected, resulting in a DoS (Denial of Service) attack.

5

Where can I find more information about CVE-2023-27530?

You can find more information about CVE-2023-27530 at the following references: [Red Hat Security Advisory](https://access.redhat.com/security/cve/CVE-2023-27530), [Ruby Advisory Database](https://github.com/rubysec/ruby-advisory-db/tree/master/gems/rack/CVE-2023-27530.yml), [Bugzilla](https://bugzilla.redhat.com/show_bug.cgi?id=2176478).

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