CVE-2024-55566

What it actually does

ColPack generates predictable temporary file names under /tmp using an unseeded RNG, enabling symlink attacks or file pre-creation that result in arbitrary file overwrites or denial of ColPack graphing availability to other users on the same system.

Why it matters to the business

Organizations using older Ubuntu systems for scientific computing or graph algorithms risk local data corruption or disrupted processing workflows when multiple users share the environment, with limited urgency given the local attack requirements and absence from known exploitation lists.

How an attack unfolds

A local attacker identifies ColPack usage, anticipates the temporary file path from the unseeded RNG, pre-creates a symlink or conflicting file in /tmp, and waits for a user-initiated graphing operation to trigger the race condition leading to overwrites or service denial.

How to fix it

Upgrade affected packages to fixed versions including linux 3.13.0-91.138 on Ubuntu 14.04 LTS, linux-aws 4.4.0-1002.2 on Ubuntu 14.04 LTS, linux 4.4.0-28.47 on Ubuntu 16.04 LTS, linux-hwe 4.8.0-36.36~16.04.1 on Ubuntu 16.04 LTS, and equivalent updates for linux-lts-xenial, linux-gke, linux-raspi2, linux-snapdragon, linux-lts-utopic, linux-lts-vivid, and linux-lts-wily packages.

How to confirm the fix worked

Confirm installed kernel and related package versions match the listed fixed releases, verify ColPack is no longer present in vulnerable 1.0.10 through 9a7293a states, and test that temporary file creation in /tmp uses non-predictable names under expected usage.

Typical attack path

1. Locate systems running vulnerable ColPack versions on shared Ubuntu hosts
2. Observe or infer ColPack process behavior to predict /tmp file names
3. Create malicious symlink or file in /tmp ahead of target execution
4. Trigger or wait for user-initiated ColPack graphing (requiring local interaction)
5. Achieve file overwrite or graphing unavailability

How to detect it

Review system logs and /tmp directory listings for unexpected file creations or modifications coinciding with ColPack processes, and examine user activity around graphing operations for signs of pre-existing conflicting files.

What your security team should do

• Prioritize upgrades of all listed Ubuntu kernel packages to the specified fixed versions
• Audit shared systems for ColPack usage and restrict local access where possible
• Enable mount options such as nosymfollow or private /tmp namespaces to reduce symlink risks
• Monitor package update channels for any additional ColPack-specific patches