CVE-2026-9494

ubuntu-pro-client Information Disclosure via Cleartext Bearer Token Exposure in Process Command Line

Published Jul 16, 2026 CVSS 3.1 · 5.5 Medium EPSS < 1% KEV · Not listed
Description
An information disclosure vulnerability exists in Canonical ubuntu-pro-client (formerly ubuntu-advantage-tools). The client validates Ubuntu Pro APT credentials by executing /usr/lib/apt/apt-helper using the download-file command. During this process, the secret bearer token is embedded directly in
the cleartext URL component passed via the command-line arguments (argv), resulting in a URL format such as https://bearer:<token>@esm.ubuntu.com/.../. On systems utilizing a default-mounted /proc file system where process-hiding mitigations (such as hidepid) are disabled, an unprivileged local attacker can
monitor system processes and read the sensitive bearer token directly from /proc/cmdline while the helper process is actively running. This leaked token can subsequently be used to gain unauthorized access to the victim's Ubuntu Pro or Expanded Security Maintenance (ESM) repositories.

Remediation

No solution or workaround provided in the CVE record

Tracking

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Advisories

Source ID Title
Ubuntu USN Ubuntu USN USN-8555-1 Ubuntu Advantage Tools (pro client) vulnerabilities
References
History
Type Values Removed Values Added
First Time appeared Canonical
Canonical ubuntu
Canonical ubuntu-pro-client
Vendors & Products Canonical
Canonical ubuntu
Canonical ubuntu-pro-client
Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

Type Values Removed Values Added
Description An information disclosure vulnerability exists in Canonical ubuntu-pro-client (formerly ubuntu-advantage-tools). The client validates Ubuntu Pro APT credentials by executing /usr/lib/apt/apt-helper using the download-file command. During this process, the secret bearer token is embedded directly in the cleartext URL component passed via the command-line arguments (argv), resulting in a URL format such as https://bearer:<token>@esm.ubuntu.com/.../. On systems utilizing a default-mounted /proc file system where process-hiding mitigations (such as hidepid) are disabled, an unprivileged local attacker can monitor system processes and read the sensitive bearer token directly from /proc/cmdline while the helper process is actively running. This leaked token can subsequently be used to gain unauthorized access to the victim's Ubuntu Pro or Expanded Security Maintenance (ESM) repositories.
Title ubuntu-pro-client Information Disclosure via Cleartext Bearer Token Exposure in Process Command Line
Weaknesses CWE-214
References
Metrics cvssV3_1

{'score': 5.5, 'vector': 'CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N'}

Weaknesses

Sources

Status
PUBLISHED
Assigner
canonical
Published
Updated
Jul 16, 2026, 3:11 PM
Reserved
May 25, 2026, 8:23 AM
Status
Awaiting Analysis
Published
Jul 16, 2026, 1:16 PM
Modified
Jul 16, 2026, 4:19 PM