CVE-2021-43854

Published: Dic 23, 2021 Last Modified: Nov 21, 2024 EU-VD ID: EUVD-2021-0148 Aliases: GHSA-f8m6-h2c7-8h9x, PYSEC-2021-859
ExploitDB:
Other exploit source:
Google Dorks:
HIGH 7,5
Source: [email protected]
Attack Vector: network
Attack Complexity: low
Privileges Required: none
User Interaction: none
Scope: unchanged
Confidentiality: none
Integrity: none
Availability: high
MEDIUM 5,0
Source: [email protected]
Access Vector: network
Access Complexity: low
Authentication: none
Confidentiality: none
Integrity: none
Availability: partial

Description

AI Translation Available

NLTK (Natural Language Toolkit) is a suite of open source Python modules, data sets, and tutorials supporting research and development in Natural Language Processing. Versions prior to 3.6.5 are vulnerable to regular expression denial of service (ReDoS) attacks. The vulnerability is present in PunktSentenceTokenizer, sent_tokenize and word_tokenize. Any users of this class, or these two functions, are vulnerable to the ReDoS attack. In short, a specifically crafted long input to any of these vulnerable functions will cause them to take a significant amount of execution time. If your program relies on any of the vulnerable functions for tokenizing unpredictable user input, then we would strongly recommend upgrading to a version of NLTK without the vulnerability. For users unable to upgrade the execution time can be bounded by limiting the maximum length of an input to any of the vulnerable functions. Our recommendation is to implement such a limit.

EPSS (Exploit Prediction Scoring System)

Trend Analysis

EPSS (Exploit Prediction Scoring System)

Prevede la probabilità di sfruttamento basata su intelligence sulle minacce e sulle caratteristiche della vulnerabilità.

EPSS Score
0,0084
Percentile
0,7th
Updated

EPSS Score Trend (Last 90 Days)

400

Uncontrolled Resource Consumption

Draft
Abstraction: Class Structure: Simple
Common Consequences
Security Scopes Affected:
Availability Access Control Other
Potential Impacts:
Dos: Crash, Exit, Or Restart Dos: Resource Consumption (Cpu) Dos: Resource Consumption (Memory) Dos: Resource Consumption (Other) Bypass Protection Mechanism Other
Applicable Platforms
All platforms may be affected
Likelihood of Exploit: High
View CWE Details
Application

Nltk by Nltk

Product Information
Vendor Nltk
Product Nltk
Version Range Affected
To 3.6.5 (exclusive)
cpe:2.3:a:nltk:nltk:*:*:*:*:*:*:*:*
Common Platform Enumeration - Standardized vulnerability identification
https://github.com/nltk/nltk/commit/1405aad979c6b8080dbbc8e…
Patch Third Party Advisory
https://github.com/nltk/nltk/commit/1405aad979c6b8080dbbc8e0858f89b2e3690341
https://github.com/nltk/nltk/issues/2866
Exploit Issue Tracking Patch Third Party Advisory
https://github.com/nltk/nltk/issues/2866
https://github.com/nltk/nltk/pull/2869
Exploit Patch Third Party Advisory
https://github.com/nltk/nltk/pull/2869
https://github.com/nltk/nltk/security/advisories/GHSA-f8m6-…
Exploit Patch Third Party Advisory
https://github.com/nltk/nltk/security/advisories/GHSA-f8m6-h2c7-8h9x
https://github.com/nltk/nltk/commit/1405aad979c6b8080dbbc8e…
Patch Third Party Advisory
https://github.com/nltk/nltk/commit/1405aad979c6b8080dbbc8e0858f89b2e3690341
https://github.com/nltk/nltk/issues/2866
Exploit Issue Tracking Patch Third Party Advisory
https://github.com/nltk/nltk/issues/2866
https://github.com/nltk/nltk/pull/2869
Exploit Patch Third Party Advisory
https://github.com/nltk/nltk/pull/2869
https://github.com/nltk/nltk/security/advisories/GHSA-f8m6-…
Exploit Patch Third Party Advisory
https://github.com/nltk/nltk/security/advisories/GHSA-f8m6-h2c7-8h9x