Underscore has unlimited recursion in _.flatten and _.isEqual, potential for DoS attack

Description

In simple words, some programs that use _.flatten or _.isEqual could be made to crash. Someone who wants to do harm may be able to do this on purpose. This can only be done if the program has special properties. It only works in Underscore versions up to 1.13.7. A more detailed explanation follows.

In affected versions of Underscore, the _.flatten and _.isEqual functions use recursion without a depth limit.

Recommendation

Update the underscore package to the latest compatible version. Followings are version details:

• Affected version(s): <= 1.13.7
• Patched version(s): 1.13.8

References

• GHSA-qpx9-hpmf-5gmw
• underscorejs.org
• CVE-2026-27601
• CWE-674
• CWE-770
• CAPEC-310
• OWASP 2021-A6

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Tags:

npm

underscore