CVE-2025-7707 World-Writable NLTK Cache Directory Vulnerability in run-llama/llama_index
Local attackers can tamper with world-writable NLTK cache files in llama_index, causing denial of service or privilege escalation.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2025-7707?
CVE-2025-7707 is a high-severity vulnerability in run-llama/llama_index, published on 13 Oct 2025. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
The llama_index library version 0.12.33 sets the NLTK data directory to a subdirectory of the codebase by default, which is world-writable in multi-user environments. This configuration allows local users to overwrite, delete, or corrupt NLTK data files, leading to potential denial of service, data tampering, or privilege escalation. The vulnerability arises from the use of a shared cache directory instead of a user-specific one, making it susceptible to local data tampering and denial of service.
Weakness: CWE-377
Which versions are affected by CVE-2025-7707?
3 open source packages ship an affected version, including llama-index. It affects 1 product.
| Package | Affected | Fixed in |
|---|---|---|
llama-index PyPI | All versions | 0.13.0 |
llama-index PyPI | All versions | 0.13.0 |
llama-index PyPI | All versions | 0.13.0 |
Products include Llamaindex Llamaindex.
How do I fix CVE-2025-7707?
Upgrade llama-index to 0.13.0 or later.
Is CVE-2025-7707 being exploited?
There is no known exploitation of CVE-2025-7707 in the wild and no public exploit code.
Other vulnerabilities in run-llama/llama_index
Sources
Also known as GHSA-rg9h-vx28-xxp5, PYSEC-2026-1556.