Vercel Ships Coordinated Next.js Security Release Patching 13 Advisories Across DoS, Middleware Bypass, SSRF and Cache Poisoning
Next.js 15.5.18 and 16.2.6 land with a 13-advisory bundle covering a React Server Components DoS (CVE-2026-23870), middleware-bypass routes, SSRF, and cache poisoning; Vercel says the WAF cannot reliably block them.
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