What is CVE-2026-9494?
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:@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.
The record classifies CVE-2026-9494 under weakness class CWE-214. Its CVSS v3 base vector states that the flaw requires local access to the host, needs low-privilege credentials, needs no user interaction, and has high impact on confidentiality. 8 affected-product entries are recorded, across 1 vendor, listed below. The identifier was first published 101 days ago.
Severity and exploitation probability
- CVSS v3.1 base score
- 5.5 — MEDIUM
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N - EPSS (FIRST)
- 0.1% probability of exploitation in the next 30 days, higher than 3.3% of all scored CVEs
- CISA KEV
- Not listed in the CISA Known Exploited Vulnerabilities catalog
- Threadlinqs priority
- 2.9/10 — a Threadlinqs composite of the CVSS base score, the EPSS percentile and public exploit availability
- Published
- 2026-07-16
Is CVE-2026-9494 being exploited?
It currently carries a trending score of 14 in the Threadlinqs vulnerability feed.
Affected products and versions
- Canonical: ubuntu-pro-client (ubuntu-advantage-tools), Ubuntu 26.04 LTS, Ubuntu 24.04 LTS, Ubuntu 22.04 LTS, Ubuntu 20.04 LTS, Ubuntu 18.04 LTS, Ubuntu 16.04 LTS, Ubuntu 14.04 LTS
How to fix CVE-2026-9494
No vendor patch reference has been recorded for CVE-2026-9494 in the tracked sources. Follow the references below for a fix, and treat the products listed above as exposed until the vendor states otherwise.
Threat activity tracking CVE-2026-9494
1 tracked threat in the Threadlinqs corpus references CVE-2026-9494, either in the campaign’s CVE list or as an indicator on the campaign record.
Sources
Enriched from CVE.org, NVD, FIRST EPSS, GitHub Security Advisories. Last verified by Threadlinqs on . This product uses the NVD API but is not endorsed or certified by the NVD.