underscore-1.9.1.tgz: 2 vulnerabilities (highest severity is: 7.5)

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Vulnerable Library - underscore-1.9.1.tgz

JavaScript's functional programming helper library.

Library home page: https://registry.npmjs.org/underscore/-/underscore-1.9.1.tgz

Vulnerabilities

Vulnerability	Severity	CVSS	Dependency	Type	Fixed in (underscore version)	Remediation Possible**	Reachability
CVE-2026-27601	High	7.5	underscore-1.9.1.tgz	Direct	1.13.8	❌
CVE-2021-23358	Low	3.3	underscore-1.9.1.tgz	Direct	1.12.1	❌

**In some cases, Remediation PR cannot be created automatically for a vulnerability despite the availability of remediation

Details

CVE-2026-27601

Vulnerable Library - underscore-1.9.1.tgz

JavaScript's functional programming helper library.

Library home page: https://registry.npmjs.org/underscore/-/underscore-1.9.1.tgz

Dependency Hierarchy:

• ❌ underscore-1.9.1.tgz (Vulnerable Library)

Found in base branch: main

Vulnerability Details

Underscore.js is a utility-belt library for JavaScript. Prior to 1.13.8, the _.flatten and _.isEqual functions use recursion without a depth limit. Under very specific conditions, detailed below, an attacker could exploit this in a Denial of Service (DoS) attack by triggering a stack overflow. Untrusted input must be used to create a recursive datastructure, for example using JSON.parse, with no enforced depth limit. The datastructure thus created must be passed to _.flatten or _.isEqual. In the case of _.flatten, the vulnerability can only be exploited if it is possible for a remote client to prepare a datastructure that consists of arrays at all levels AND if no finite depth limit is passed as the second argument to _.flatten. In the case of _.isEqual, the vulnerability can only be exploited if there exists a code path in which two distinct datastructures that were submitted by the same remote client are compared using _.isEqual. For example, if a client submits data that are stored in a database, and the same client can later submit another datastructure that is then compared to the data that were saved in the database previously, OR if a client submits a single request, but its data are parsed twice, creating two non-identical but equivalent datastructures that are then compared. Exceptions originating from the call to _.flatten or _.isEqual, as a result of a stack overflow, are not being caught. This vulnerability is fixed in 1.13.8.

Publish Date: 2026-03-03

URL: CVE-2026-27601

CVSS 3 Score Details (7.5)

Base Score Metrics:

• Exploitability Metrics:
  • Attack Vector: Network
  • Attack Complexity: Low
  • Privileges Required: None
  • User Interaction: None
  • Scope: Unchanged
• Impact Metrics:
  • Confidentiality Impact: None
  • Integrity Impact: None
  • Availability Impact: High

For more information on CVSS3 Scores, click here.

Suggested Fix

Type: Upgrade version

Release Date: 2026-03-03

Fix Resolution: 1.13.8

CVE-2021-23358

Vulnerable Library - underscore-1.9.1.tgz

JavaScript's functional programming helper library.

Library home page: https://registry.npmjs.org/underscore/-/underscore-1.9.1.tgz

Dependency Hierarchy:

• ❌ underscore-1.9.1.tgz (Vulnerable Library)

Found in base branch: main

Vulnerability Details

The package underscore from 1.13.0-0 and before 1.13.0-2, from 1.3.2 and before 1.12.1 are vulnerable to Arbitrary Code Injection via the template function, particularly when a variable property is passed as an argument as it is not sanitized.

Publish Date: 2021-03-29

URL: CVE-2021-23358

CVSS 3 Score Details (3.3)

Base Score Metrics:

• Exploitability Metrics:
  • Attack Vector: Network
  • Attack Complexity: High
  • Privileges Required: High
  • User Interaction: None
  • Scope: Unchanged
• Impact Metrics:
  • Confidentiality Impact: Low
  • Integrity Impact: Low
  • Availability Impact: None

For more information on CVSS3 Scores, click here.

Suggested Fix

Type: Upgrade version

Origin: https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-23358

Release Date: 2021-03-29

Fix Resolution: 1.12.1