Vulnerability in Vercel Next.js

CVE-2022-21721

Next.js is a React framework. Starting with version 12.0.0 and prior to version 12.0.9, vulnerable code could allow a bad actor to trigger a denial of service attack for anyone using i18n functionality. In order to be affected by this CVE, one must use next start or a custom server and the built-in i18n support. Deployments on Vercel, along with similar environments where invalid requests are filtered before reaching Next.js, are not affected. A patch has been released, `next@12.0.9`, that mitigates this issue. As a workaround, one may ensure `/${locale}/_next/` is blocked from reaching the Next.js instance until it becomes feasible to upgrade.

Published · last modified .

CVSS v3 metric

CVSS v3 base score 5.9 (Medium). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H.

EPSS exploit prediction

EPSS: 0.022 (81.4th percentile), scored .

Low probability of exploitation in the next 30 days, but still tracked. 81st percentile — 81.4% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2022-21721: held from 0.022 to 0.022.

EPSS over last 30 days · oldest: 0.022 · newest: 0.022 · change: 0.000

Affected products

Public proof-of-concept exploits

References

Frequently asked questions

What is CVE-2022-21721?
CVE-2022-21721 is a medium-severity vulnerability in Vercel Next.js. CVSS score: 5.9/10. Published 2022-01-28.
How severe is CVE-2022-21721?
Medium severity. CVSS v3 base score is 5.9 out of 10.
Is CVE-2022-21721 known to be exploited?
1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.