GravitLauncher LaunchServer <=5.7.11 - Unauthenticated Path Traversal to Arbitrary File Read

LaunchServer's Netty FileServerHandler computes the served path by stripping one leading character on the assumption that every request-target begins with '/'. Netty's HttpServerCodec accepts a request-target without a leading slash verbatim, so a request without a leading slash bypasses path...

CVE-2026-54617

GravitLauncher LaunchServer (open-source Minecraft launcher) is vulnerable to an unauthenticated path traversal in its HTTP file server (FileServerHandler.channelRead0) on port 9274 , which is enabled by default and bound to 0.0.0.0. The root cause is a substring(1) that strips the first characte...

CVE-2026-54617: Improper Limitation of a Pathname to a Restricted Directory

GravitLauncher is an open-source Minecraft launcher based on sashok724's v3. Prior to 5.7.12, an unauthenticated remote actor can send a raw HTTP request target without a leading slash to the default LaunchServer file server on port 9274. FileServerHandler.channelRead0 in...

LaunchServer FileServerHandler has an unauthenticated path traversal issue

Summary An unauthenticated path traversal in the LaunchServer HTTP file server FileServerHandler lets any remote actor read any file readable by the LaunchServer process e.g. ../../../../etc/passwd. This is a generic arbitrary-file-read primitive, so the fix must address the traversal itself, not...

GHSA-5G75-477J-2C2F LaunchServer FileServerHandler has an unauthenticated path traversal issue

Summary An unauthenticated path traversal in the LaunchServer HTTP file server FileServerHandler lets any remote actor read any file readable by the LaunchServer process e.g. ../../../../etc/passwd. This is a generic arbitrary-file-read primitive, so the fix must address the traversal itself, not...

PT-2026-55363

Summary An unauthenticated path traversal in the LaunchServer HTTP file server FileServerHandler lets any remote actor read any file readable by the LaunchServer process e.g. ../../../../etc/passwd. This is a generic arbitrary-file-read primitive, so the fix must address the traversal itself, not...

PT-2026-55482

Name of the Vulnerable Software and Affected Versions GravitLauncher versions prior to 5.7.12 Description An unauthenticated remote actor can perform a path traversal attack via the LaunchServer HTTP file server. By sending a raw HTTP request target without a leading slash to port 9274, an attack...