Link Following Affecting nltk package, versions <3.10.3-1


Severity

Recommended
0.0
high
0
10

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Threat Intelligence

EPSS
0.14% (4th percentile)

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  • Snyk IDSNYK-DEBIANUNSTABLE-NLTK-19385591
  • published28 Aug 2026
  • disclosed27 Aug 2026

Introduced: 27 Aug 2026

NewCVE-2026-81727  (opens in a new tab)
CWE-59  (opens in a new tab)

How to fix?

Upgrade Debian:unstable nltk to version 3.10.3-1 or higher.

NVD Description

Note: Versions mentioned in the description apply only to the upstream nltk package and not the nltk package as distributed by Debian. See How to fix? for Debian:unstable relevant fixed versions and status.

NLTK versions before 3.10.3 contain a filesystem containment bypass vulnerability in the Downloader.download and Downloader.incr_download methods that allows attackers to overwrite files outside the install root through pre-existing hardlinks. Attackers with write access to a shared downloader directory can create hardlinks pointing to outside-root files that are then overwritten during normal package extraction, mutating files outside the intended install tree.

CVSS Base Scores

version 3.1