FFmpeg v.n6.1-3-g466799d4f5 allows an attacker to trigger use of a parameter of negative size in the av_samples_set_silence function in thelibavutil/samplefmt.c:260:9 component.
A stack-based buffer overflow condition is a condition where the buffer being overwritten is allocated on the stack (i.e., is a local variable or, rarely, a parameter to a function).