Unreal Resource Management: A raw uasset Encryption Scheme
source: https://en.imzlp.com/posts/32412/ version: 【非官方】第三方博客 Z's Blog，引用 Core/Public/UObject/ObjectVersion.h 源码 fetched: 2026-10-11 (curl)
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Unreal Resource Management: A raw uasset Encryption Scheme | Z's Blog (NON-OFFICIAL)
nd content in games. Different resource types, such as textures, models, and animation sequences, are converted into UE’s uasset resources for access and editing within the engine. Tools like WinHex64 can be used to view uasset files in binary format: The first four bytes of the uasset file are the PACKAGE_FILE_TAG : It is a fixed value: Core/Public/UObject/ObjectVersion.h 1 2 # define PACKAGE_FILE_TAG 0x9E2A83C1 # define PACKAGE_FILE_TAG_SWAPPED 0xC1832A9E Used to identify whether the file is a uasset resource; when the engine attempts to load the resource, it will first check this TAG. If it is 0x9E2A83C1 , it will be considered a resource, and then subsequent serialization actions will occur. In simple terms, if encryption is not considered, the only way to make the resources unrecognizable in other engines is to change the first four bytes of the uasset file header to another magic number. Summary Serialization When the first four bytes of the file are detected as PACKAGE_FILE_TAG being 0x9E2A83C1 , the serialized data will be read from the disk to construct a PackageFileSummary structure. After debugging, here is the data for the PackageFileSummary: The PackageFileSummary is also serialized directly into the uasset file header, starting from byte 0: However, the engine does not serialize the entire PackageFileSummary entirely; it serializes each attribute individually, meaning it varies depending on the engine version, different settings, and resource situations. Thus, it is not a fixed size of data. Taking the Summary data shown in the screenshot as an example, once serialized, I listed the attributes and the byte order of serialization: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 Tag(int32) 0x9E2A83C1 C1832A9F 0x9E