CVE-2026-39324

EIP tracks 2 public exploits for CVE-2026-39324. PoCs published by adminlove520, sm1ee.

AI-analyzed exploit summary This repository contains a functional exploit PoC for CVE-2026-39324, demonstrating a session forgery vulnerability in Rack::Session::Cookie where unencrypted cookies are accepted despite the presence of secrets. The exploit includes a vulnerable server, verification script, and attack script to forge session cookies without knowing any secret.

Rack::Session is a session management implementation for Rack. From 2.0.0 to before 2.1.2, Rack::Session::Cookie incorrectly handles decryption failures when configured with secrets:. If cookie decryption fails, the implementation falls back to a default decoder instead of rejecting the cookie. This allows an unauthenticated attacker to supply a crafted session cookie that is accepted as valid session data without knowledge of any configured secret. Because this mechanism is used to load session state, an attacker can manipulate session contents and potentially gain unauthorized access. This vulnerability is fixed in 2.1.2.