AirSane is a SANE frontend, and a scanner server that supports Apple's AirScan protocol. Versions prior to 0.4.12 have a vulnerability in the custom HTTP server implementation of AirSane that allows a remote unauthenticated attacker to cause a Denial of Service (DoS) via memory exhaustion (OOM). In httpserver.cpp, the HttpServer::Request::content function reads the Content-Length header and directly passes this value to std::string::resize() without any upper-bound validation or safe parsing.
An attacker can send an HTTP POST request with an artificially large Content-Length value. This forces the daemon to attempt allocating gigabytes of memory, resulting in a std::bad_alloc exception and immediately crashing the AirSane process. Additionally, providing non-numeric characters in the Content-Length header leads to undefined behavior (NaN to integer conversion) due to the lack of error handling during header parsing.
Version 0.4.12 patches the issue.
Attack Parameters
Impact Assessment
CVSS Vector v3.1