UBUNTU-CVE-2026-32762

    Dashboard / Vulnerabilities / UBUNTU-CVE-2026-32762

    UBUNTU-CVE-2026-32762

    Published: 2 Apr 2026Last Modified: 4 Nov 2026
    Upstream:
    CVE-2026-32762

    Summary:

    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: https://ubuntu.com/security/CVE-2026-32762, https://www.cve.org/CVERecord?id=CVE-2026-32762, https://github.com/rack/rack/security/advisories/GHSA-qfgr-crr9-7r49, https://ubuntu.com/security/notices/USN-8182-1, https://ubuntu.com/security/notices/USN-8989-1

    Affected packages

    Package

    Name: ruby-rack

    Purl: pkg:deb/ubuntu/ruby-rack?arch=source&distro=questing

    Affected ranges

    Type: ECOSYSTEM

    Events:

    Introduced- 0
    Fixed -3.1.16-0.1ubuntu0.3

    Affected versions

    2.2.7-1.1

    Common Vulnerability Scoring System

    Attack Vector
    Network
    Adjacent
    Local
    Physical
    Privileges Required
    None
    Low
    High
    User Interaction
    None
    Required
    Scope
    Unchanged
    Changed
    Confidentiality
    None
    Low
    High
    Integrity
    None
    Low
    High
    Availability
    None
    Low
    High
    UBUNTU-CVE-2026-32762 | CVE-DB