Server-side Request Forgery (SSRF) Affecting nltk package, versions [,3.10.3)
Threat Intelligence
The probability is the direct output of the EPSS model, and conveys an overall sense of the threat of exploitation in the wild. The percentile measures the EPSS probability relative to all known EPSS scores. Note: This data is updated daily, relying on the latest available EPSS model version. Check out the EPSS documentation for more details.
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- published25 Aug 2026
- disclosed25 Aug 2026
- creditsondt99
Introduced: 25 Aug 2026
NewCVE-2026-78682 (opens in a new tab)How to fix?
Upgrade nltk to version 3.10.3 or higher.
Overview
nltk is a Natural Language Toolkit (NLTK) is a Python package for natural language processing.
Affected versions of this package are vulnerable to Server-side Request Forgery (SSRF) via the urlopen process in nltk/pathsec.py. An attacker can reach internal-only HTTP resources by supplying a URL that passes local validation and then fetching it through a configured proxy, which performs the actual egress outside NLTK’s pinning path. This lets an attacker read loopback, link-local, or private network content through callers such as nltk.data.load and downloader fetch paths, causing internal data exposure and allowing the application to retrieve and process forged downloader content.