CVE-2026-81727 (GCVE-0-2026-81727)
Vulnerability from cvelistv5
Published
2026-08-27 14:51
Modified
2026-08-27 17:43
Severity ?
6.9 (Medium) - CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:H/VA:H/SC:N/SI:N/SA:N
7.1 (High) - CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:H
CWE
  • CWE-59 - Improper Link Resolution Before File Access ('Link Following')
Summary
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.
References
Impacted products
Vendor Product Version
nltk nltk Version: 0   ≤
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