+ "details": "### Summary\nDecompressing invalid LZ4 data can leak data from uninitialized memory, or can leak content from previous decompression operations when reusing an output buffer.\n\n### Details\nThe LZ4 block format defines a \"match copy operation\" which duplicates previously written data or data from the user-supplied dict. The position of that data is defined by an _offset_. The data is copied within the output buffer from the _offset_ to the current output position.\nHowever, lz4_flex did not properly detect invalid and out-of-bounds _offset_ values properly, causing it to copy uninitialized data from the output buffer.\n\nOnly the block based API functions are affected: \n`lz4_flex::block::{decompress_into, decompress_into_with_dict}`\n\nWhen safe-decode is disabled _additionally_ these functions are affected\n`lz4_flex::block::{decompress, decompress_with_dict, decompress_size_prepended, decompress_size_prepended_with_dict}`\n\nAll `frame` APIs are _not_ affected.\n\nThere are two affected use cases:\n- decompressing LZ4 data with the `unsafe` implementation (`safe-decode` feature flag disabled, which is enabled by default):\ncan leak content of uninitialized memory as decompressed result\n- decompressing LZ4 data into a reused, user-supplied `output` buffer (affects the `safe-decode` feature as well):\ncan leak the previous contents of the output buffer as decompressed result\n\n### Impact\nLeakage of data from uninitialized memory or content from previous decompression operations, possibly revealing sensitive information and secrets.\n\n### Mitigation\nlz4_flex 0.12.1 and 0.11.6 fixes this issue without requiring changes in user code.\n\nIf you cannot upgrade, you can mitigate this vulnerability by zeroing the output buffer before calling `block::decompress_into` or `block::decompress_into_with_dict` (only block based API is affected, frame API is not affected). Additionally the the `safe-decode` feature flag should be enabled.",
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