CVE-2026-9494

Summary

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.

Affected Software

VendorProductVersion RangeStatus
Canonicalubuntu-pro-client (ubuntu-advantage-tools)0 < 37.3affected
CanonicalUbuntu 26.04 LTS37.2ubuntu0.1unaffected
CanonicalUbuntu 24.04 LTS37.2ubuntu~24.04.1unaffected
CanonicalUbuntu 22.04 LTS37.2ubuntu~22.04.1unaffected
CanonicalUbuntu 20.04 LTS37.1ubuntu0~20.04.1unaffected
CanonicalUbuntu 18.04 LTS37.1ubuntu0~18.04.1unaffected
CanonicalUbuntu 16.04 LTS37.1ubuntu0~16.04.1unaffected
CanonicalUbuntu 14.04 LTS19.7ubuntu0.1unaffected

Weaknesses

  • CWE-214: CWE-214 Invocation of process using visible sensitive information

ADP Enrichment

CISA ADP Vulnrichment

  • SSVC:
  • Exploitation: none
    • Automatable: no
    • Technical Impact: partial

References