7.5High
CVE-2026-92596
Nodemailer before 9.1.0 contains a quadratic time complexity vulnerability in the addressparser component that allows remote attackers to cause denial of service by supplying a crafted comma-separated address list. Attackers can send a single email with a large number of addresses to block the Node.js event loop for extended periods, consuming 100% CPU and freezing the process.
What this means for your business
- An attacker can use it remotely, over a network, without a login, and without anyone at your company clicking anything.
What to do
- 1Ask your IT team or provider whether any of your systems use the affected product.
- 2If you do, follow the vendor's guidance. No patch reference has been published yet.
Not sure if your company is exposed?
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Scoring
- CVSS
- 7.5 (v3.1)
- Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H- CVSS v4
- 8.7
- Weakness
- CWE-400
- Assigned by
- disclosure@vulncheck.com
Dates
- Published
- 2026-09-16
- Last modified
- 2026-09-17
- Sources
- NVD
References
- https://github.com/nodemailer/nodemailer/commit/34da642
- https://github.com/nodemailer/nodemailer/commit/7cc38af
- https://github.com/nodemailer/nodemailer/commit/83b8c48
- https://github.com/nodemailer/nodemailer/commit/9116da9
- https://github.com/nodemailer/nodemailer/security/advisories/GHSA-2x7j-588g-ccc2
- https://www.vulncheck.com/advisories/nodemailer-before-9.1.0-denial-of-service-via-addressparser
- https://github.com/nodemailer/nodemailer/security/advisories/GHSA-2x7j-588g-ccc2