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
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See something that needs correcting? Let us knowUpdated May 05, 2026