Next.js - Authorization Bypass (CVE-2025-29927)

CVE-2025-29927 is a high-severity vulnerability affecting the NextJS React framework, which allows attackers to bypass authorization checks when these controls are enforced through application middleware.

CrowdSec has been tracking this vulnerability and its exploits since 24th of March 2025.

According to CrowdSec data, while opportunistic exploitation dominates, a portion of threat actors trying to exploit CVE-2025-29927 apply basic targeting methods such as port or service detection. This indicates emerging patterns of selective targeting. CrowdSec network telemetry also shows that exploitation of CVE-2025-29927 has significantly declined over the past week. Attack volumes are well below the long-term average, suggesting attackers are rapidly losing interest. The vulnerability appears to be falling out of active use across most threat landscapes.

Attack patterns are tailored towards application endpoints that rely on middleware-based authorization within NextJS deployments.