High severity · published Dec 10, 2021
CVE-2021-43803
Next.js is a React framework
7.5
CVSS
47.3%
EPSS
No
On KEV
Description
Next.js is a React framework. In versions of Next.js prior to 12.0.5 or 11.1.3, invalid or malformed URLs could lead to a server crash. In order to be affected by this issue, the deployment must use Next.js versions above 11.1.0 and below 12.0.5, Node.js above 15.0.0, and next start or a custom server. Deployments on Vercel are not affected, along with similar environments where invalid requests are filtered before reaching Next.js. Versions 12.0.5 and 11.1.3 contain patches for this issue.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
None
Integrity
None
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)47.3% · higher than 99% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
NE
Next.js · Vercel
11.1.0 before 11.1.3; 12.0.0 before 12.0.5 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-43803
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-43803
Patch
https://github.com/vercel/next.js/commit/6d98b4fb4315dec1badecf0e9bdc212a4272b264
Patch
https://github.com/vercel/next.js/pull/32080
Release Notes
https://github.com/vercel/next.js/releases/tag/v11.1.3
Release Notes
https://github.com/vercel/next.js/releases/v12.0.5
Patch
https://github.com/vercel/next.js/security/advisories/GHSA-25mp-g6fv-mqxx
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