CVE-2026-62383

Description

A flaw was found in nltk. A local attacker can exploit a symlink-based vulnerability in the IPIPANCorpusReader methods. By placing a symbolic link in the corpus root directory and invoking specific methods, an attacker can bypass security validation and read arbitrary files accessible to the process. This could lead to unauthorized information disclosure.

Statement

The nltk library is vulnerable to information disclosure, allowing an attacker with local access and low privileges to read arbitrary files. This occurs if an attacker can place a symlink within the nltk corpus root directory, bypassing path validation and enabling access to sensitive data with the permissions of the running process.

Mitigation

To mitigate this vulnerability, restrict write access to the `IPIPANCorpusReader` corpus root directory. Ensure that only trusted users or processes have permissions to create or modify files within this directory. This prevents an attacker from placing malicious symlinks that could lead to arbitrary file disclosure.

Common Vulnerability Scoring System (CVSS) Score Details

Info alert:Important note

CVSS scores for open source components depend on vendor-specific factors (e.g. version or build chain). Therefore, Red Hat's score and impact rating can be different from NVD and other vendors. Red Hat remains the authoritative CVE Naming Authority (CNA) source for its products and services (see Red Hat classifications).

The following CVSS metrics and score provided are preliminary and subject to review.

CVSS v3 Score Breakdown

Red HatNVDcve.org
Base Score5.5N/A5.5
Attack VectorLocalN/ALocal
Attack ComplexityLowN/ALow
Privileges RequiredLowN/ALow
User InteractionNoneN/ANone
ScopeUnchangedN/AUnchanged
ConfidentialityHighN/AHigh
Integrity ImpactNoneN/ANone
Availability ImpactNoneN/ANone

Vector

Red Hat: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N

cve.org: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N

Understanding the Weakness (CWE)

Integrity,Confidentiality,Availability

Technical Impact: Execute Unauthorized Code or Commands

The attacker may be able to create or overwrite critical files that are used to execute code, such as programs or libraries.

Integrity

Technical Impact: Modify Files or Directories

The attacker may be able to overwrite or create critical files, such as programs, libraries, or important data. If the targeted file is used for a security mechanism, then the attacker may be able to bypass that mechanism. For example, appending a new account at the end of a password file may allow an attacker to bypass authentication.

Confidentiality

Technical Impact: Read Files or Directories

The attacker may be able read the contents of unexpected files and expose sensitive data. If the targeted file is used for a security mechanism, then the attacker may be able to bypass that mechanism. For example, by reading a password file, the attacker could conduct brute force password guessing attacks in order to break into an account on the system.

Availability

Technical Impact: DoS: Crash, Exit, or Restart

The attacker may be able to overwrite, delete, or corrupt unexpected critical files such as programs, libraries, or important data. This may prevent the product from working at all and in the case of protection mechanisms such as authentication, it has the potential to lock out product users.

Frequently Asked Questions

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