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Advisory details: pypa / nltk/PYSEC-0000-CVE-2026-62383
Advisory ID pypa/nltk/PYSEC-0000-CVE-2026-62383
Aliases CVE-2026-62383
GHSA-3hhw-38pf-pxj6
PYSEC-0000-CVE-2026-62383
Summary nltk versions before 3.10.2 contain a symlink-based arbitrary file read vulnerability in IPIPANCorpusReader methods that bypass nltk.pathsec validation entirely. Attackers can place a symlink in the corpus root directory and read arbitrary files accessible to the process by calling channels(), domains(), categories(), or fileids() methods with the symlink filename.
Status Published
Exploitability 0.5
Weighted Severity 6.1
Risk 3.0
Affected and Fixed Packages Package Details
Introduced and Fixed Package Commit Patches Package Commit Patches Details
Weaknesses (0)
There are no known CWE.
System Score Found at
cvssv4 6.8 https://github.com/pypa/advisory-database/blob/main/vulns/nltk/PYSEC-0000-CVE-2026-62383.yaml
Reference id Reference type URL
https://github.com/nltk/nltk/security/advisories/GHSA-3hhw-38pf-pxj6
https://www.vulncheck.com/advisories/nltk-ipipancorpusreader-symlink-arbitrary-file-read
No exploits are available.

No EPSS data available for this advisory.

Patch URL
There are no known patches.
Vector: CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X Found at https://github.com/pypa/advisory-database/blob/main/vulns/nltk/PYSEC-0000-CVE-2026-62383.yaml
Attack Vector (AV) Attack Complexity (AC) Attack Requirements (AT) Privileges Required (PR) User Interaction (UI) Vulnerable System Impact Confidentiality (VC) Vulnerable System Impact Integrity (VI) Vulnerable System Impact Availability (VA) Subsequent System Impact Confidentiality (SC) Subsequent System Impact Integrity (SI) Subsequent System Impact Availability (SA)

network

adjacent

local

physical

low

high

none

present

none

low

high

none

passive

active

high

low

none

high

low

none

high

low

none

high

low

none

high

low

none

high

low

none

Vector: SSVCv2/E:N/A:N/T:P/P:M/B:A/M:M/D:T/2026-08-26T15:55:30Z/

Decision: Track

Source URL: https://github.com/cisagov/vulnrichment/blob/develop/2026/62xxx/CVE-2026-62383.json

Source Advisory: vulnrichment/CVE-2026-62383

View SSVC decision tree 
[{'Exploitation': 'none'},
 {'Automatable': 'no'},
 {'Technical Impact': 'partial'},
 {'Mission Prevalence': 'minimal'},
 {'Public Well-being Impact': 'material'},
 {'Mission & Well-being': 'medium'}]