Next.js Patches Critical AVIF and Windows Flaws Enabling Unauthenticated RCE
Vercel patches two critical Next.js unauthenticated RCE flaws: a libheif AVIF heap overflow (CVSS 9.5) and a Windows path traversal (CVE-2026-75604).
Vercel patched two critical Next.js flaws enabling unauthenticated remote code execution: a heap buffer overflow in libheif's AVIF image scaling (GHSA-2xp9-vwfh-vxw4, CVSS v4 9.5) and a Windows path traversal (CVE-2026-75604, CVSS 9.0). The AVIF flaw affects only sites explicitly enabling AVIF optimization and overwrites roughly 16,384 bytes past the buffer; the path traversal affects Windows-hosted Next.js deployments on versions 13.4-15.5.23 and 16.0-16.3.2. Fixes shipped in Next.js 15.5.24 and 16.3.3 on August 25, 2026, with the AVIF researchers releasing a Python PoC demonstrating RCE on multiple applications. No exploitation had been reported as of August 27, 2026.
Active Exploitation Attempts Target WSO2 API Manager JWT Bypass With Forged Admin Tokens
watchTowr observed active exploitation of CVE-2026-5430, a WSO2 API Manager JWT bypass using forged admin tokens, risking credential theft and account takeover.
CVE-2026-5430 (CVSS 9.8-10.0), an improper cryptographic signature verification flaw in WSO2 API Manager, lets JWT authentication be bypassed with unsupported algorithms, enabling administrative account takeover. watchTowr honeypots captured forged JWT tokens with baked-in administrator privileges on September 13, 2026, which could expose API credentials, consumer keys, and secrets for every registered application. Affected products include WSO2 API Manager 4.1.0-4.6.0, API Control Plane, Traffic Manager, and Universal Gateway. Fixes are available via GitHub pull requests and subscription update levels, and users are urged to patch immediately.