CVE-2023-27530: Input Validation
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
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
Upgrade
redhat/pcsto a version that resolves this vulnerability.Fixed in 0:0.10.15-4.el8_8.1 - Upgrade
Upgrade
redhat/pcsto a version that resolves this vulnerability.Fixed in 0:0.10.8-1.el8_4.4 - Upgrade
Upgrade
redhat/pcsto a version that resolves this vulnerability.Fixed in 0:0.10.12-6.el8_6.4 - Upgrade
Upgrade
redhat/pcsto a version that resolves this vulnerability.Fixed in 0:0.11.4-7.el9_2 - Upgrade
Upgrade
redhat/pcsto a version that resolves this vulnerability.Fixed in 0:0.11.1-10.el9_0.4 - Upgrade
Upgrade
redhat/rubygem-rackto a version that resolves this vulnerability.Fixed in 3.0.4.2 - Upgrade
Upgrade
redhat/rubygem-rackto a version that resolves this vulnerability.Fixed in 2.2.6.3 - Upgrade
Upgrade
redhat/rubygem-rackto a version that resolves this vulnerability.Fixed in 2.1.4.3 - Upgrade
Upgrade
redhat/rubygem-rackto a version that resolves this vulnerability.Fixed in 2.0.9.3 - Upgrade
Upgrade
rubygems/rackto a version that resolves this vulnerability.Fixed in 3.0.4.2 - Upgrade
Upgrade
rubygems/rackto a version that resolves this vulnerability.Fixed in 2.2.6.3 - Upgrade
Upgrade
rubygems/rackto a version that resolves this vulnerability.Fixed in 2.1.4.3 - Upgrade
Upgrade
rubygems/rackto a version that resolves this vulnerability.Fixed in 2.0.9.3 - Upgrade
Upgrade
debian/ruby-rackto a version that resolves this vulnerability.Fixed in 2.2.22-0+deb12u1Fixed in 2.2.22-0+deb12u2Fixed in 3.1.20-0+deb13u1Fixed in 3.1.20-0+deb13u2Fixed in 3.2.7-1Fixed in 3.2.8-1 - Upgrade
Upgrade
Rackto a version that resolves this vulnerability.Fixed in 3.0.4.2 - Upgrade
Upgrade
Rackto a version that resolves this vulnerability.Fixed in 2.2.6.3 - Upgrade
Upgrade
Rackto a version that resolves this vulnerability.Fixed in 2.1.4.3 - Upgrade
Upgrade
Rackto a version that resolves this vulnerability.Fixed in 2.0.9.3 - Compensating control
Configure a proxy to limit the POST body size to mitigate the multipart MIME parsing denial-of-service vulnerability.
Event History
Parent advisories
This vulnerability appears in the following advisories.
Frequently Asked Questions
What is the vulnerability ID?
The vulnerability ID is CVE-2023-27530.
What is the severity of CVE-2023-27530?
The severity of CVE-2023-27530 is high.
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.
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.
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).