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CVE-2026-12391 Detail

Description

An insecure symlink following vulnerability exists in Canonical ubuntu-pro-client (formerly ubuntu-advantage-tools) within the pro collect-logs command framework. The utility creates or utilizes predictable temporary file paths or user-accessible log directories when gathering diagnostic information without verifying the file type or ownership. An unprivileged local attacker can exploit this behavior by creating a symbolic link (symlink) at a predictable destination path pointing to an arbitrary, root-readable file (such as /etc/shadow or private files within /root). When a root administrator or operator subsequently executes the pro collect-logs command, the tool follows the user-controlled symlink, reads the target file, and compresses its contents into the resulting diagnostic support archive. Because the output archive remains readable by the unprivileged user, the attacker can extract and read the sensitive root-owned files, leading to a complete information disclosure of system secrets.


Metrics

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CVSS 4.0 Severity and Vector Strings:

NIST CVSS score
NIST: NVD
N/A
NVD assessment not yet provided.

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URL Source(s) Tag(s)
Canonical Ltd.

Weakness Enumeration

CWE-ID CWE Name Source
CWE-59 Improper Link Resolution Before File Access ('Link Following') Canonical Ltd.  

Change History

2 change records found show changes

Quick Info

CVE Dictionary Entry:
CVE-2026-12391
NVD Published Date:
07/16/2026
NVD Last Modified:
07/16/2026
Source:
Canonical Ltd.