Commit e0941f6abb for ffmpeg

commit e0941f6abba868eff5cdad37eef422342c520e63
Author: Michael Niedermayer <michael@niedermayer.cc>
Date:   Tue Oct 6 06:50:59 2026 +0200

    avformat/mxg: Fail on truncated marker segments

    The fix is the one recommended in the report.

    Fixes: use of uninitialized memory
    Fixes: 544YKgP8DNSj
    Fixes: AISLE-2026-0111-00027
    Use of uninitialized memory Replicated through UnModified FFmpeg with Valgrind
    Found-by: Joshua Rogers <joshua.rogers@aisle.com>

diff --git a/libavformat/mxg.c b/libavformat/mxg.c
index 40139d7d3d..5595d7d270 100644
--- a/libavformat/mxg.c
+++ b/libavformat/mxg.c
@@ -203,6 +203,8 @@ static int mxg_read_packet(AVFormatContext *s, AVPacket *pkt)
                     ret = mxg_update_cache(s, size);
                     if (ret < 0)
                         return ret;
+                    if (mxg->cache_size < size)
+                        return AVERROR_EOF;
                     startmarker_ptr = mxg->buffer_ptr - 2;
                     mxg->cache_size = 0;
                 } else {