CVE-2026-3449

Severity: low (CVSS 3.3 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.1% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-03-03 · updated 2026-06-17
Weakness: CWE-705

Description

Versions of the package @tootallnate/once before 3.0.1 are vulnerable to Incorrect Control Flow Scoping in promise resolving when AbortSignal option is used. The Promise remains in a permanently pending state after the signal is aborted, causing any await or .then() usage to hang indefinitely. This can cause a control-flow leak that can lead to stalled requests, blocked workers, or degraded application availability.

Affected products

@tootallnate/once: before 3.0.1 — fixed in 3.0.1

How to fix

Upgrade to a fixed version: @tootallnate/once 3.0.1. Check the vendor advisory for mitigations.

References

https://github.com/TooTallNate/once/commit/b9f43cc5259bee2952d91ad3cdbd201a82df448a
https://github.com/TooTallNate/once/issues/8
https://security.snyk.io/vuln/SNYK-JS-TOOTALLNATEONCE-15250612

Get alerted when CVE-2026-3449 or the next vulnerability affects your stack