ISOMAN

CVE

CVE-2026-12391

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.

Severity
MEDIUM
CVSS
5
Published
Modified

Linked Releases

DistributionReleaseStatusEvidence
Ubuntu26.04 amd64 desktopunknownsource
Ubuntu26.04 amd64 live-serverunknownsource
Ubuntu24.04.4 amd64 desktopunknownsource
Ubuntu24.04.4 amd64 live-serverunknownsource
Ubuntu24.04.3 amd64 live-serverunknownsource
Ubuntu22.04.5 amd64 desktopunknownsource
Ubuntu22.04.5 amd64 live-serverunknownsource
Ubuntu20.04.6 amd64 desktopunknownsource
Ubuntu20.04.6 amd64 live-serverunknownsource
Ubuntu18.04.6 amd64 desktopunknownsource
Ubuntu18.04.6 amd64 live-serverunknownsource
Ubuntu16.04.7 amd64 desktopunknownsource
Ubuntu16.04.6 i386 desktopunknownsource
Ubuntu16.04.7 amd64 serverunknownsource
Ubuntu16.04.6 i386 serverunknownsource
Ubuntu24.04 amd64 beta-desktopunknownsource
Ubuntu24.04 amd64 beta-live-serverunknownsource
Ubuntu24.04unknownsource
Ubuntu24.04 arm64 beta-live-serverunknownsource
Ubuntu24.04 ppc64el beta-live-serverunknownsource
Ubuntu24.04 riscv64unknownsource
Ubuntu24.04 s390x beta-live-serverunknownsource
Ubuntu24.04 amd64 desktopunknownsource
Ubuntu24.04 amd64 live-serverunknownsource
Ubuntu24.04 arm64 live-serverunknownsource
Ubuntu24.04 ppc64el live-serverunknownsource
Ubuntu24.04 s390x live-serverunknownsource
Ubuntu24.04.1 amd64 desktopunknownsource
Ubuntu24.04.1 amd64 live-serverunknownsource
Ubuntu24.04.1unknownsource
Ubuntu24.04.1 arm64 live-serverunknownsource
Ubuntu24.04.1 ppc64el live-serverunknownsource
Ubuntu24.04.1 riscv64unknownsource
Ubuntu24.04.1 s390x live-serverunknownsource
Ubuntu24.04.2 amd64 desktopunknownsource
Ubuntu24.04.2 amd64 live-serverunknownsource
Ubuntu24.04.2unknownsource
Ubuntu24.04.2 arm64 live-serverunknownsource
Ubuntu24.04.2 ppc64el live-serverunknownsource
Ubuntu24.04.2 riscv64unknownsource
Ubuntu24.04.2 s390x live-serverunknownsource
Ubuntu26.04.1 amd64 desktopunknownsource
Ubuntu26.04.1 amd64 live-serverunknownsource

References

  1. https://ubuntu.com/security/CVE-2026-12391