Full Report
Yet another tiny, crucial piece of volunteer software begets a big problem.
Analysis Summary
# Vulnerability: Remote Code Execution via Malicious CD-Indexing Cue Files
## CVE Details
- CVE ID: CVE-2023-43641
- CVSS Score: 8.8 (High) (GitHub submission rating)
- CWE: Memory Corruption (Out-of-bounds array writing)
## Affected Systems
- Products: libcue library (used for parsing .cue files)
- Versions: All versions of libcue prior to the patch. This affects Linux systems running the GNOME desktop environment where the Tracker Miner service automatically indexes files.
- Configurations: Systems must have the GNOME Tracker Miner service enabled and running, and the user must trigger the parsing of a malicious `.cue` file (e.g., by downloading it).
## Vulnerability Description
The vulnerability is a memory corruption flaw, specifically an out-of-bounds array writing issue, present in the `libcue` library responsible for parsing CD-indexing cue sheets (`.cue` files). If a user downloads and the GNOME Tracker Miner service attempts to index the malicious cue file, the flawed parsing logic allows an attacker to execute arbitrary code on the system.
## Exploitation
- Status: PoC available (Demonstrated by GitHub Security Lab executing a calculator pop-up)
- Complexity: Low (Described as a "one-click" exploit triggered by file indexing)
- Attack Vector: Network (Triggered by downloading a malicious file that is subsequently read by the indexing service)
## Impact
- Confidentiality: High (Arbitrary code execution can lead to data theft)
- Integrity: High (Arbitrary code execution allows modification of system files)
- Availability: High (Arbitrary code execution can lead to system compromise/denial of service)
## Remediation
### Patches
- Users must update the `libcue` library to a patched version, which Linux distributions will then incorporate into system updates.
- Users should apply updates released by their specific Linux distribution addressing this vulnerability (e.g., updates for the Tracker Miner or libcue components).
### Workarounds
- Disable the GNOME Tracker Miner service temporarily until operating system patches can be applied.
- Avoid downloading or opening `.cue` files from untrusted sources.
## Detection
- Indicators of Compromise: Unexpected execution of processes or programs immediately following the opening or indexing of a newly downloaded file, particularly `.cue` files.
- Detection methods and tools: Monitoring file system events related to `.cue` file creation/modification and subsequent process execution by the Tracker Miner/indexing service.
## References
- Vendor advisories: GitHub Security Lab coordinated disclosure on October 9th.
- Relevant links: hxxps://arstechnica.com/information-technology/2023/10/one-click-remote-code-exploit-in-cd-cue-files-affects-most-gnome-based-linux-distros/
- Relevant links: hxxps://github.blog/2023-10-09-coordinated-disclosure-1-click-rce-on-gnome-cve-2023-43641/