UBUNTU-CVE-2026-34827

See a problem?
Please try reporting it to the source first.

Source

https://ubuntu.com/security/CVE-2026-34827

Import Source

https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-34827.json

JSON Data

https://api.osv.dev/v1/vulns/UBUNTU-CVE-2026-34827

Upstream

CVE-2026-34827

Downstream

USN-8182-1

Related

USN-8182-1

Published

2026-04-02T18:16:00Z

Modified

2026-04-27T18:57:08.148464Z

Severity

7.5 (High) CVSS_V3 - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H CVSS Calculator
Ubuntu - medium

Summary

[none]

Details

Rack is a modular Ruby web server interface. From versions 3.0.0.beta1 to before 3.1.21, and 3.2.0 to before 3.2.6, Rack::Multipart::Parser#handlemimehead parses quoted multipart parameters such as Content-Disposition: form-data; name="..." using repeated String#index searches combined with String#slice! prefix deletion. For escape-heavy quoted values, this causes super-linear processing. An unauthenticated attacker can send a crafted multipart/form-data request containing many parts with long backslash-escaped parameter values to trigger excessive CPU usage during multipart parsing. This results in a denial of service condition in Rack applications that accept multipart form data. This issue has been patched in versions 3.1.21 and 3.2.6.

References

Affected packages

Ubuntu:22.04:LTS

ruby-rack

Package

Name: ruby-rack
Purl: pkg:deb/ubuntu/ruby-rack@2.1.4-5ubuntu1.2?arch=source&distro=jammy

Affected ranges

Type: ECOSYSTEM
Events: Introduced

0Unknown introduced version / All previous versions are affected

Affected versions

2.*

2.1.4-3

2.1.4-4

2.1.4-5

2.1.4-5ubuntu1

2.1.4-5ubuntu1.1

2.1.4-5ubuntu1.2

Ecosystem specific

{
    "binaries": [
        {
            "binary_name": "ruby-rack",
            "binary_version": "2.1.4-5ubuntu1.2"
        }
    ]
}

Database specific

source

"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-34827.json"

Ubuntu:24.04:LTS

ruby-rack

Package

Name: ruby-rack
Purl: pkg:deb/ubuntu/ruby-rack@2.2.7-1ubuntu0.7?arch=source&distro=noble

Affected ranges

Type: ECOSYSTEM
Events: Introduced

0Unknown introduced version / All previous versions are affected

Affected versions

2.*

2.2.4-3

2.2.7-1

2.2.7-1ubuntu0.1

2.2.7-1ubuntu0.2

2.2.7-1ubuntu0.3

2.2.7-1ubuntu0.4

2.2.7-1ubuntu0.5

2.2.7-1ubuntu0.6

2.2.7-1ubuntu0.7

Ecosystem specific

{
    "binaries": [
        {
            "binary_name": "ruby-rack",
            "binary_version": "2.2.7-1ubuntu0.7"
        }
    ]
}

Database specific

source

"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-34827.json"

Ubuntu:25.10

ruby-rack

Package

Name: ruby-rack
Purl: pkg:deb/ubuntu/ruby-rack@3.1.16-0.1ubuntu0.3?arch=source&distro=questing

Affected ranges

Type: ECOSYSTEM
Events: Introduced

0Unknown introduced version / All previous versions are affected

Fixed

3.1.16-0.1ubuntu0.3

Affected versions

2.*

2.2.7-1.1

3.*

3.1.16-0.1

3.1.16-0.1ubuntu0.1

3.1.16-0.1ubuntu0.2

Ecosystem specific

{
    "binaries": [
        {
            "binary_name": "ruby-rack",
            "binary_version": "3.1.16-0.1ubuntu0.3"
        }
    ],
    "availability": "No subscription required"
}

Database specific

source

"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-34827.json"

Ubuntu:26.04

ruby-rack

Package

Name: ruby-rack
Purl: pkg:deb/ubuntu/ruby-rack@3.2.4-1ubuntu1?arch=source&distro=resolute

Affected ranges

Type: ECOSYSTEM
Events: Introduced

0Unknown introduced version / All previous versions are affected

Affected versions

3.*

3.1.16-0.1

3.1.18-1

3.1.18-1build1

3.2.4-1ubuntu1

Ecosystem specific

{
    "binaries": [
        {
            "binary_name": "ruby-rack",
            "binary_version": "3.2.4-1ubuntu1"
        }
    ]
}

Database specific

source

"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-34827.json"

Ubuntu:Pro:14.04:LTS

ruby-rack

Package

Name: ruby-rack
Purl: pkg:deb/ubuntu/ruby-rack@1.5.2-3+deb8u3ubuntu1~esm11?arch=source&distro=esm-infra-legacy/trusty

Affected ranges

Type: ECOSYSTEM
Events: Introduced

0Unknown introduced version / All previous versions are affected

Affected versions

1.*

1.5.2-1

1.5.2-1ubuntu0.1~esm1

1.5.2-3+deb8u3ubuntu1~esm2

1.5.2-3+deb8u3ubuntu1~esm3

1.5.2-3+deb8u3ubuntu1~esm4

1.5.2-3+deb8u3ubuntu1~esm6

1.5.2-3+deb8u3ubuntu1~esm7

1.5.2-3+deb8u3ubuntu1~esm8

1.5.2-3+deb8u3ubuntu1~esm9

1.5.2-3+deb8u3ubuntu1~esm10

1.5.2-3+deb8u3ubuntu1~esm11

Ecosystem specific

{
    "binaries": [
        {
            "binary_name": "librack-ruby",
            "binary_version": "1.5.2-3+deb8u3ubuntu1~esm11"
        },
        {
            "binary_name": "librack-ruby1.8",
            "binary_version": "1.5.2-3+deb8u3ubuntu1~esm11"
        },
        {
            "binary_name": "librack-ruby1.9.1",
            "binary_version": "1.5.2-3+deb8u3ubuntu1~esm11"
        },
        {
            "binary_name": "ruby-rack",
            "binary_version": "1.5.2-3+deb8u3ubuntu1~esm11"
        }
    ]
}

Database specific

source

"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-34827.json"

Ubuntu:Pro:16.04:LTS

ruby-rack

Package

Name: ruby-rack
Purl: pkg:deb/ubuntu/ruby-rack@1.6.4-3ubuntu0.2+esm10?arch=source&distro=esm-apps/xenial

Affected ranges

Type: ECOSYSTEM
Events: Introduced

0Unknown introduced version / All previous versions are affected

Affected versions

1.*

1.5.2-4

1.6.4-2

1.6.4-3

1.6.4-3ubuntu0.1

1.6.4-3ubuntu0.2

1.6.4-3ubuntu0.2+esm1

1.6.4-3ubuntu0.2+esm2

1.6.4-3ubuntu0.2+esm4

1.6.4-3ubuntu0.2+esm5

1.6.4-3ubuntu0.2+esm6

1.6.4-3ubuntu0.2+esm7

1.6.4-3ubuntu0.2+esm8

1.6.4-3ubuntu0.2+esm9

1.6.4-3ubuntu0.2+esm10

Ecosystem specific

{
    "binaries": [
        {
            "binary_name": "ruby-rack",
            "binary_version": "1.6.4-3ubuntu0.2+esm10"
        }
    ]
}

Database specific

source

"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-34827.json"

Ubuntu:Pro:18.04:LTS

ruby-rack

Package

Name: ruby-rack
Purl: pkg:deb/ubuntu/ruby-rack@1.6.4-4ubuntu0.2+esm10?arch=source&distro=esm-apps/bionic

Affected ranges

Type: ECOSYSTEM
Events: Introduced

0Unknown introduced version / All previous versions are affected

Affected versions

1.*

1.6.4-4

1.6.4-4ubuntu0.1

1.6.4-4ubuntu0.2

1.6.4-4ubuntu0.2+esm1

1.6.4-4ubuntu0.2+esm2

1.6.4-4ubuntu0.2+esm4

1.6.4-4ubuntu0.2+esm5

1.6.4-4ubuntu0.2+esm6

1.6.4-4ubuntu0.2+esm7

1.6.4-4ubuntu0.2+esm8

1.6.4-4ubuntu0.2+esm9

1.6.4-4ubuntu0.2+esm10

Ecosystem specific

{
    "binaries": [
        {
            "binary_name": "ruby-rack",
            "binary_version": "1.6.4-4ubuntu0.2+esm10"
        }
    ]
}

Database specific

source

"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-34827.json"

Ubuntu:Pro:20.04:LTS

ruby-rack

Package

Name: ruby-rack
Purl: pkg:deb/ubuntu/ruby-rack@2.0.7-2ubuntu0.1+esm10?arch=source&distro=esm-apps/focal

Affected ranges

Type: ECOSYSTEM
Events: Introduced

0Unknown introduced version / All previous versions are affected

Affected versions

2.*

2.0.6-3

2.0.7-2

2.0.7-2ubuntu0.1

2.0.7-2ubuntu0.1+esm1

2.0.7-2ubuntu0.1+esm2

2.0.7-2ubuntu0.1+esm3

2.0.7-2ubuntu0.1+esm4

2.0.7-2ubuntu0.1+esm5

2.0.7-2ubuntu0.1+esm6

2.0.7-2ubuntu0.1+esm7

2.0.7-2ubuntu0.1+esm8

2.0.7-2ubuntu0.1+esm9

2.0.7-2ubuntu0.1+esm10

Ecosystem specific

{
    "binaries": [
        {
            "binary_name": "ruby-rack",
            "binary_version": "2.0.7-2ubuntu0.1+esm10"
        }
    ]
}

Database specific

source

"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-34827.json"