underscore.js needs to be updated because of CVE-2026-27601

[Hexmage]

Preconditions and environment

• Magento version: All of them including the current 2.4.9 alpha

Steps to reproduce

underscore.js has an security vulnerability which can potentially be abused to Ddos the website in certain scenario's ( CVE-2026-27601).

This has been fixed in 1.13.8 but the latest version in the repo is 1.13.7/

Expected result

n/a

Actual result

n/a

Additional information

No response

Release note

No response

Triage and priority

• Severity: S0 - Affects critical data or functionality and leaves users without workaround.
• Severity: S1 - Affects critical data or functionality and forces users to employ a workaround.
• Severity: S2 - Affects non-critical data or functionality and forces users to employ a workaround.
• Severity: S3 - Affects non-critical data or functionality and does not force users to employ a workaround.
• Severity: S4 - Affects aesthetics, professional look and feel, “quality” or “usability”.

[m2-assistant]

Hi @Hexmage. Thank you for your report.
To speed up processing of this issue, make sure that the issue is reproducible on the vanilla Magento instance following Steps to reproduce.

• For more details, review the Magento Contributor Assistant documentation.
• Add a comment to assign the issue: @magento I am working on this
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[github-jira-sync-bot]

✅ Jira issue https://jira.corp.adobe.com/browse/AC-17349 is successfully created for this GitHub issue.