CVE-2021-3828

Inefficient Regular Expression Complexity in nltk/nltk

View on CVE.org

Published Sep 27, 2021 CVSS 3.1 · 7.5 High EPSS 1.6% KEV · Not listed

Description

nltk is vulnerable to Inefficient Regular Expression Complexity

Affected Products

Default status is the baseline for the product, each version can override it (e.g. patched versions marked unaffected).

Vendor Product Default status Versions

nltk

nltk/nltk

affected

Version	Status	Constraints
`unspecified`	affected	≤ 3.6.3

Configuration 1 [-]

cpe:2.3:a:nltk:nltk:*:*:*:*:*:*:*:*

No data.

No data available yet.

Remediation

No solution or workaround provided in the CVE record

Tracking

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Advisories

Source	ID	Title
EUVD	EUVD-2021-0147	nltk is vulnerable to Inefficient Regular Expression Complexity
Github GHSA	GHSA-2ww3-fxvq-293j	NLTK Vulnerable to REDoS
Ubuntu USN	USN-5215-1	NLTK vulnerability

Metrics

No CVSS v4.0

Attack Vector Network

Attack Complexity Low

Privileges Required None

Scope Unchanged

Confidentiality Impact None

Integrity Impact None

Availability Impact High

User Interaction None

Attack Vector Network

Attack Complexity Low

Privileges Required None

Scope Unchanged

Confidentiality Impact None

Integrity Impact None

Availability Impact High

User Interaction None

Access Vector Network

Access Complexity Low

Authentication None

Confidentiality Impact None

Integrity Impact None

Availability Impact Partial

This CVE is not in the KEV list.

Exploit prediction score: 1.6% (1.592% probability within 30 days)

Key SSVC decision points have not yet been added.

References

Link	Providers
https://github.com/nltk/nltk/commit/277711ab1dec729e626b27aab6fa35ea5efbd7e6
https://huntr.dev/bounties/d19aed43-75bc-4a03-91a0-4d0bb516bc32

History

No history.

Subscriptions

Nltk Nltk

Weaknesses

Sources

CVE record Updated: Aug 3, 2024, 5:09 PM

Status: PUBLISHED
Assigner: @huntrdev
Published: Sep 27, 2021, 12:25 PM
Updated: Aug 3, 2024, 5:09 PM
Reserved: Sep 24, 2021, 12:00 AM

View source JSON

Vulnrichment No data

No data.

NVD Updated: Jun 17, 2026, 4:05 AM

Status: Modified
Published: Sep 27, 2021, 1:15 PM
Modified: Jun 17, 2026, 4:05 AM

View source JSON

Red Hat No data

No data.

OpenCVE enrichment No data

No data.

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