An issue was discovered in Squid before 4.10. Due to incorrect input validation, the NTLM authentication credentials parser in ext_lm_group_acl may write to memory outside the credentials buffer. On systems with memory access protections, this can result in the helper process being terminated unexpectedly. This leads to the Squid process also terminating and a denial of service for all clients using the proxy.
An issue was discovered in Squid before 4.10. Due to incorrect buffer management, a remote client can cause a buffer overflow in a Squid instance acting as a reverse proxy.
An issue was discovered in Squid before 4.10. It allows a crafted FTP server to trigger disclosure of sensitive information from heap memory, such as information associated with other users' sessions or non-Squid processes.
An issue was discovered in Squid before 4.10. Due to incorrect input validation, it can interpret crafted HTTP requests in unexpected ways to access server resources prohibited by earlier security filters.