# CVE-2026-11386: ubuntu-advantage-pro: An input validation and injection vulnerability exists in Canonical ubuntu-pro-client (formerly ubuntu-advantage-tools)

CVE-2026-11386 is fixed in 5 products on 1 platform, first by ubuntu-advantage-pro 37.2ubuntu0.1, released July 17, 2026. It is not reported as exploited. Patch Radar priority: High.

- Web page: https://patchblox.com/security/cve/CVE-2026-11386
- Priority: High
- CVSS: n/a (High)
- EPSS: 0.0053
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Jul 17, 2026

## Description

An input validation and injection vulnerability exists in Canonical ubuntu-pro-client (formerly ubuntu-advantage-tools). The client constructs APT source files (such as /etc/apt/sources.list.d/ubuntu-.list or their DEB822 equivalents) using data received directly from the contract server response via the directives.suites[] and directives.aptURL fields. Because the client utilizes Python's str.format() to write these files without performing escaping, validation, or newline character filtering, a malicious or tampered contract response containing embedded newline (\n) characters can successfully inject arbitrary, attacker-controlled deb configuration lines into root-owned APT sources. When combined with the unvalidated additionalPackages[] field—which is passed positionally into a root-executed apt-get install command—an attacker capable of spoofing or manipulating the contract response (e.g., via a compromised internal infrastructure, an intercepted connection utilizing a trusted CA, or local logical bugs) can force the client to fetch and install malicious packages. This ultimately leads to arbitrary code execution with root privileges on the affected system. This component is preinstalled on supported Ubuntu Server releases and auto-attaches by default on cloud provider Ubuntu Pro images.

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Linux | ubuntu-advantage-pro Ubuntu 22.04.1 LTS (jammy) | 37.2ubuntu~22.04.1 | [ubuntu-advantage-pro 37.2ubuntu~22.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-jammy-ubuntu-advantage-pro-37.2ubuntu-22.04.1.md) | Jul 18, 2026 |
| Linux | ubuntu-advantage-pro Ubuntu 24.04.5 LTS (noble) | 37.2ubuntu~24.04.1 | [ubuntu-advantage-pro 37.2ubuntu~24.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-noble-ubuntu-advantage-pro-37.2ubuntu-24.04.1.md) | Jul 18, 2026 |
| Linux | ubuntu-advantage-pro Ubuntu 26.04.1 LTS (resolute) | 37.2ubuntu0.1 | [ubuntu-advantage-pro 37.2ubuntu0.1](https://patchblox.com/security/data/fix/linux/ubuntu-resolute-ubuntu-advantage-pro-37.2ubuntu0.1.md) | Jul 17, 2026 |
| Linux | ubuntu-advantage-tools Ubuntu 22.04.1 LTS (jammy) | 37.2ubuntu~22.04.1 | [ubuntu-advantage-tools 37.2ubuntu~22.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-jammy-ubuntu-advantage-tools-37.2ubuntu-22.04.1.md) | Jul 18, 2026 |
| Linux | ubuntu-advantage-tools Ubuntu 24.04.5 LTS (noble) | 37.2ubuntu~24.04.1 | [ubuntu-advantage-tools 37.2ubuntu~24.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-noble-ubuntu-advantage-tools-37.2ubuntu-24.04.1.md) | Jul 18, 2026 |
| Linux | ubuntu-advantage-tools Ubuntu 26.04.1 LTS (resolute) | 37.2ubuntu0.1 | [ubuntu-advantage-tools 37.2ubuntu0.1](https://patchblox.com/security/data/fix/linux/ubuntu-resolute-ubuntu-advantage-tools-37.2ubuntu0.1.md) | Jul 17, 2026 |
| Linux | ubuntu-pro-auto-attach Ubuntu 22.04.1 LTS (jammy) | 37.2ubuntu~22.04.1 | [ubuntu-pro-auto-attach 37.2ubuntu~22.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-jammy-ubuntu-pro-auto-attach-37.2ubuntu-22.04.1.md) | Jul 18, 2026 |
| Linux | ubuntu-pro-auto-attach Ubuntu 24.04.5 LTS (noble) | 37.2ubuntu~24.04.1 | [ubuntu-pro-auto-attach 37.2ubuntu~24.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-noble-ubuntu-pro-auto-attach-37.2ubuntu-24.04.1.md) | Jul 18, 2026 |
| Linux | ubuntu-pro-auto-attach Ubuntu 26.04.1 LTS (resolute) | 37.2ubuntu0.1 | [ubuntu-pro-auto-attach 37.2ubuntu0.1](https://patchblox.com/security/data/fix/linux/ubuntu-resolute-ubuntu-pro-auto-attach-37.2ubuntu0.1.md) | Jul 17, 2026 |
| Linux | ubuntu-pro-client Ubuntu 22.04.1 LTS (jammy) | 37.2ubuntu~22.04.1 | [ubuntu-pro-client 37.2ubuntu~22.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-jammy-ubuntu-pro-client-37.2ubuntu-22.04.1.md) | Jul 18, 2026 |
| Linux | ubuntu-pro-client Ubuntu 24.04.5 LTS (noble) | 37.2ubuntu~24.04.1 | [ubuntu-pro-client 37.2ubuntu~24.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-noble-ubuntu-pro-client-37.2ubuntu-24.04.1.md) | Jul 18, 2026 |
| Linux | ubuntu-pro-client Ubuntu 26.04.1 LTS (resolute) | 37.2ubuntu0.1 | [ubuntu-pro-client 37.2ubuntu0.1](https://patchblox.com/security/data/fix/linux/ubuntu-resolute-ubuntu-pro-client-37.2ubuntu0.1.md) | Jul 17, 2026 |
| Linux | ubuntu-pro-client-l10n Ubuntu 22.04.1 LTS (jammy) | 37.2ubuntu~22.04.1 | [ubuntu-pro-client-l10n 37.2ubuntu~22.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-jammy-ubuntu-pro-client-l10n-37.2ubuntu-22.04.1.md) | Jul 18, 2026 |
| Linux | ubuntu-pro-client-l10n Ubuntu 24.04.5 LTS (noble) | 37.2ubuntu~24.04.1 | [ubuntu-pro-client-l10n 37.2ubuntu~24.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-noble-ubuntu-pro-client-l10n-37.2ubuntu-24.04.1.md) | Jul 18, 2026 |
| Linux | ubuntu-pro-client-l10n Ubuntu 26.04.1 LTS (resolute) | 37.2ubuntu0.1 | [ubuntu-pro-client-l10n 37.2ubuntu0.1](https://patchblox.com/security/data/fix/linux/ubuntu-resolute-ubuntu-pro-client-l10n-37.2ubuntu0.1.md) | Jul 17, 2026 |

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Data as of 2026-11-09T01:18:40Z UTC. Source: Patchblox Patch Radar (https://patchblox.com/security/patch-radar). Patchblox finds out-of-date software on Windows, macOS and Linux and updates it through release rings: https://patchblox.com/demo

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