Vulnerabilities

Tinyproxy through 1.11.3 is vulnerable to HTTP request parsing desynchronization due to a case-sensitive comparison of the Transfer-Encoding header in src/reqs.c. The is_chunked_transfer function uses strcmp to compare the header value against "chunked", even though RFC 7230 specifies that transfer-coding names are case-insensitive.

Tinyproxy through 1.11.2 contains an integer overflow vulnerability in the strip_return_port() function within src/reqs.c.

A use-after-free vulnerability exists in the HTTP Connection Headers parsing in Tinyproxy 1.11.1 and Tinyproxy 1.10.0. A specially crafted HTTP header can trigger reuse of previously freed memory, which leads to memory corruption and could lead to remote code execution. An attacker needs to make an unauthenticated HTTP request to trigger this vulnerability.

Potential leak of left-over heap data if custom error page templates containing special non-standard variables are used. Tinyproxy commit 84f203f and earlier use uninitialized buffers in process_request() function.

main.c in Tinyproxy 1.8.4 and earlier creates a /run/tinyproxy/tinyproxy.pid file after dropping privileges to a non-root account, which might allow local users to kill arbitrary processes by leveraging access to this non-root account for tinyproxy.pid modification before a root script executes a "kill `cat /run/tinyproxy/tinyproxy.pid`" command.