UBUNTU-CVE-2026-32762

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Source
https://ubuntu.com/security/CVE-2026-32762
Import Source
https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-32762.json
JSON Data
https://api.osv.dev/v1/vulns/UBUNTU-CVE-2026-32762
Upstream
  • CVE-2026-32762
Downstream
Related
Published
2026-04-02T18:16:00Z
Modified
2026-04-21T14:16:15.645042Z
Severity
  • 4.8 (Medium) CVSS_V3 - CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N 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::Utils.forwarded_values parses the RFC 7239 Forwarded header by splitting on semicolons before handling quoted-string values. Because quoted values may legally contain semicolons, a header can be interpreted by Rack as multiple Forwarded directives rather than as a single quoted for value. In deployments where an upstream proxy, WAF, or intermediary validates or preserves quoted Forwarded values differently, this discrepancy can allow an attacker to smuggle host, proto, for, or by parameters through a single header value. This issue has been patched in versions 3.1.21 and 3.2.6.

References

Affected packages

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_version": "3.1.16-0.1ubuntu0.3",
            "binary_name": "ruby-rack"
        }
    ],
    "availability": "No subscription required"
}

Database specific

source 
"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-32762.json"