Ballerina is an open source programming language and platform for cloud application programmers. Ballerina versions 1.2.x and SL releases up to alpha 3 have a potential for a supply chain attack via MiTM against users. Http connections did not make use of TLS and certificate checking was ignored. The vulnerability allows an attacker to substitute or modify packages retrieved from BC thus allowing to inject malicious code into ballerina executables. This has been patched in Ballerina 1.2.14 and Ballerina SwanLake alpha4.