CVE-2026-0846

Publication date 9 March 2026

Last updated 27 May 2026

Ubuntu priority

Cvss 3 Severity Score

Description

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

Show unmaintained releases

Package	Ubuntu Release	Status
nltk	26.04 LTS resolute	Fixed 3.9.2-1ubuntu0.1~esm2
	25.10 questing	Vulnerable
	24.04 LTS noble	Fixed 3.8.1-1ubuntu0.1~esm2
	22.04 LTS jammy	Fixed 3.7-1ubuntu0.1~esm2
	20.04 LTS focal	Fixed 3.4.5-2ubuntu0.1~esm4
	18.04 LTS bionic	Fixed 3.2.5-1ubuntu0.1+esm4
	16.04 LTS xenial	Ignored end of ESM support, was needed
	14.04 LTS trusty	Fixed 2.0~b9-0ubuntu4.1~esm6

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Patch details

For informational purposes only. We recommend not to cherry-pick updates. How can I get the fixes?

Package	Patch details
nltk	Upstream: 1fc6269 Upstream: 5c46f3d

Severity score breakdown

Parameter	Value
Base score	8.6 · High
Attack vector	Network
Attack complexity	Low
Privileges required	None
User interaction	None
Scope	Unchanged
Confidentiality	High
Integrity impact	Low
Availability impact	Low
Vector	CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:L/A:L

References

Related Ubuntu Security Notices (USN)

USN-8302-1
NLTK vulnerabilities
25 May 2026