From 43f952cf00e0ff8759f967ff95beafa92ab1b526 Mon Sep 17 00:00:00 2001
From: Brian Popow <popow@gmx.de>
Date: Mon, 23 Mar 2026 09:37:53 +0100
Subject: [PATCH] Throw InvalidImageContentException when frame control chunk
 does not have enough data

---
 src/ImageSharp/Formats/Png/Chunks/FrameControl.cs | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/src/ImageSharp/Formats/Png/Chunks/FrameControl.cs b/src/ImageSharp/Formats/Png/Chunks/FrameControl.cs
index 91f79c8154..7288df8a0e 100644
--- a/src/ImageSharp/Formats/Png/Chunks/FrameControl.cs
+++ b/src/ImageSharp/Formats/Png/Chunks/FrameControl.cs
@@ -147,7 +147,13 @@ internal readonly struct FrameControl
     /// <param name="data">The data to parse.</param>
     /// <returns>The parsed fcTL.</returns>
     public static FrameControl Parse(ReadOnlySpan<byte> data)
-        => new(
+    {
+        if (data.Length < Size)
+        {
+            PngThrowHelper.ThrowInvalidImageContentException("The Frame Control Chunk does not contain enough data!");
+        }
+
+        return new(
             sequenceNumber: BinaryPrimitives.ReadUInt32BigEndian(data[..4]),
             width: BinaryPrimitives.ReadUInt32BigEndian(data[4..8]),
             height: BinaryPrimitives.ReadUInt32BigEndian(data[8..12]),
@@ -157,4 +163,5 @@ internal readonly struct FrameControl
             delayDenominator: BinaryPrimitives.ReadUInt16BigEndian(data[22..24]),
             disposalMode: (FrameDisposalMode)(data[24] + 1),
             blendMode: (FrameBlendMode)data[25]);
+    }
 }