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.
References
Configurations
History
05 Mar 2026, 21:08
| Type | Values Removed | Values Added |
|---|---|---|
| First Time |
Underscorejs
Underscorejs underscore |
|
| CPE | cpe:2.3:a:underscorejs:underscore:*:*:*:*:*:node.js:*:* | |
| CVSS |
v2 : v3 : |
v2 : unknown
v3 : 7.5 |
| References | () https://github.com/jashkenas/underscore/commit/411e222eb0ca5d570cc4f6315c02c05b830ed2b4 - Patch | |
| References | () https://github.com/jashkenas/underscore/commit/a6e23ae9647461ec33ad9f92a2ecfc220eea0a84 - Patch | |
| References | () https://github.com/jashkenas/underscore/security/advisories/GHSA-qpx9-hpmf-5gmw - Exploit, Patch, Vendor Advisory |
03 Mar 2026, 23:15
| Type | Values Removed | Values Added |
|---|---|---|
| New CVE |
Information
Published : 2026-03-03 23:15
Updated : 2026-03-05 21:08
NVD link : CVE-2026-27601
Mitre link : CVE-2026-27601
CVE.ORG link : CVE-2026-27601
JSON object : View
Products Affected
underscorejs
- underscore
CWE
CWE-770
Allocation of Resources Without Limits or Throttling
