CVE-2026-9494 ubuntu-pro-client Information Disclosure via Cleartext Bearer Token Exposure in Process Command Line
Local attackers can read Ubuntu Pro bearer tokens from process command lines, enabling unauthorized access to ESM repositories.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-9494?
CVE-2026-9494 is a medium-severity vulnerability in Canonical Ubuntu 14.04 LTS, published on 16 Jul 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Official 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.
Weakness: CWE-214
Which versions are affected by CVE-2026-9494?
How do I fix CVE-2026-9494?
Apply the vendor's patch.
Is CVE-2026-9494 being exploited?
There is no known exploitation of CVE-2026-9494 in the wild and no public exploit code.
Sources
Also known as GHSA-4m5m-x42p-vrwg, UBUNTU-CVE-2026-9494.