What’s Vulnerable › Vulnerabilities

CVE-2025-7707: World-Writable NLTK Cache Directory Vulnerability in run-llama/llama_index

• Severity: high (CVSS 7.8 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 0.2% probability of exploitation in the next 30 days
• Public exploit or detection template: yes
• Published: 2025-10-13 · updated 2026-10-08
• Weakness: CWE-377

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.

Affected products

• run-llama/llama_index: from 0.12.33 before 0.13.0 — fixed in 0.13.0

How to fix

Upgrade to a fixed version: run-llama/llama_index 0.13.0. Check the vendor advisory for mitigations.

References

• https://github.com/run-llama/llama_index/commit/98816394d57c7f53f847ed7b60725e69d0e7aae4
• https://huntr.com/bounties/3fe2c8ab-6727-4aef-a0ef-4d2818e48803

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