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Advisory details: pypa / nltk/PYSEC-2026-97
Advisory ID pypa/nltk/PYSEC-2026-97
Aliases CVE-2026-0846
GHSA-h8wq-7xc4-p3qx
PYSEC-2026-97
Summary A vulnerability in the `filestring()` function of the `nltk.util` module in nltk version 3.9.2 allows arbitrary file read due to improper validation of input paths. The function directly opens files specified by user input without sanitization, enabling attackers to access sensitive system files by providing absolute paths or traversal paths. This vulnerability can be exploited locally or remotely, particularly in scenarios where the function is used in web APIs or other interfaces that accept user-supplied input.
Status Published
Exploitability 0.5
Weighted Severity 6.8
Risk 3.4
Affected and Fixed Packages Package Details
Introduced and Fixed Package Commit Patches Package Commit Patches Details
Weaknesses (0)
There are no known CWE.
Reference id Reference type URL
007b84f8-418e-4300-99d0-bf504c2f97eb Other https://huntr.com/bounties/007b84f8-418e-4300-99d0-bf504c2f97eb
GHSA-h8wq-7xc4-p3qx https://github.com/advisories/GHSA-h8wq-7xc4-p3qx
No exploits are available.

No EPSS data available for this advisory.

Patch URL
There are no known patches.
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N Found at https://github.com/pypa/advisory-database/blob/main/vulns/nltk/PYSEC-2026-97.yaml
Attack Vector (AV) Attack Complexity (AC) Privileges Required (PR) User Interaction (UI) Scope (S) Confidentiality Impact (C) Integrity Impact (I) Availability Impact (A)

network

adjacent_network

local

physical

low

high

none

low

high

none

required

unchanged

changed

high

low

none

high

low

none

high

low

none

Vector: SSVCv2/E:P/A:Y/T:P/P:M/B:A/M:M/D:T/2026-03-12T14:48:03Z/

Decision: Track

Source URL: https://github.com/cisagov/vulnrichment/blob/develop/2026/0xxx/CVE-2026-0846.json

Source Advisory: vulnrichment/CVE-2026-0846

View SSVC decision tree
[{'Exploitation': 'poc'},
 {'Automatable': 'yes'},
 {'Technical Impact': 'partial'},
 {'Mission Prevalence': 'minimal'},
 {'Public Well-being Impact': 'material'},
 {'Mission & Well-being': 'medium'}]

Vector: SSVCv2/E:P/A:Y/T:P/P:M/B:A/M:M/D:T/2026-03-12T14:48:03Z/

Decision: Track

Source URL: https://github.com/cisagov/vulnrichment/blob/develop/2026/0xxx/CVE-2026-0846.json

Source Advisory: vulnrichment/CVE-2026-0846

View SSVC decision tree
[{'Exploitation': 'poc'},
 {'Automatable': 'yes'},
 {'Technical Impact': 'partial'},
 {'Mission Prevalence': 'minimal'},
 {'Public Well-being Impact': 'material'},
 {'Mission & Well-being': 'medium'}]