CVE-2021-23424

Regular Expression Denial of Service (ReDoS)

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Published Aug 18, 2021 CVSS 3.1 · 7.5 High EPSS 1.8% KEV · Not listed

Description

This affects all versions of package ansi-html. If an attacker provides a malicious string, it will get stuck processing the input for an extremely long time.

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

n/a

ansi-html

affected

Version	Status	Constraints
`0`	affected	< unspecified

Configuration 1 [-]

cpe:2.3:a:ansi-html_project:ansi-html:*:*:*:*:*:node.js:*:*

No data.

No data available yet.

Remediation

No solution or workaround provided in the CVE record

Tracking

Sign in to view the affected projects.

Advisories

Source	ID	Title
EUVD	EUVD-2021-2126	This affects all versions of package ansi-html. If an attacker provides a malicious string, it will get stuck processing the input for an extremely long time.
Github GHSA	GHSA-whgm-jr23-g3j9	Uncontrolled Resource Consumption in ansi-html

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

No CVSS v3.0

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: 1.8% (1.768% probability within 30 days)

Key SSVC decision points have not yet been added.

References

Link	Providers
https://github.com/Tjatse/ansi-html/issues/19
https://nvd.nist.gov/vuln/detail/CVE-2021-23424
https://snyk.io/vuln/SNYK-JAVA-ORGWEBJARSNPM-1567198
https://snyk.io/vuln/SNYK-JS-ANSIHTML-1296849
https://www.cve.org/CVERecord?id=CVE-2021-23424

History

No history.

Subscriptions

Ansi-html Project Ansi-html

Weaknesses

Sources

CVE record Updated: Sep 16, 2024, 5:38 PM

Status: PUBLISHED
Assigner: snyk
Published: Aug 18, 2021, 4:15 PM
Updated: Sep 16, 2024, 5:38 PM
Reserved: Jan 8, 2021, 12:00 AM

View source JSON

Vulnrichment No data

No data.

NVD Updated: Jun 17, 2026, 3:38 AM

Status: Modified
Published: Aug 18, 2021, 5:15 PM
Modified: Jun 17, 2026, 3:38 AM

View source JSON

Red Hat Updated: May 7, 2021, 12:00 AM

Severity: Moderate
Public date: May 7, 2021, 12:00 AM

View source Bugzilla JSON

OpenCVE enrichment No data

No data.

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