UBUNTU-CVE-2026-125195: Low severity ubuntu/ffmpeg vulnerability

FFmpeg through 9.0.2 contains an uninitialized memory disclosure vulnerability in adpcmencodeframe() in libavcodec/adpcmenc.c that leaks heap bytes when encoding mono ADPCMMS audio with trellis enabled. Attackers submitting audio to a service using this encoding receive output packets where about half of each block contains stale heap memory from the encoding process.