abpframework/abp · error · AbpException

The encrypted BLOB is corrupted or has an invalid format: tr

Error message

The encrypted BLOB is corrupted or has an invalid format: truncated chunk!

What it means

GetCipherChunkSize requires at least ChunkLengthPrefixSize (4) bytes for the length prefix. Fewer than that means the chunk header was cut off mid-prefix — the stream ended partway through reading the length, so the chunk is truncated and cannot be parsed.

Source

Thrown at framework/src/Volo.Abp.BlobStoring/Volo/Abp/BlobStoring/BlobEncryptionCodec.cs:531

        if (chunkIndex < 0)
        {
            // A wrapped chunk index would repeat a nonce for the same key, which breaks AES-GCM.
            throw new AbpException("The data is too large: the maximum chunk count has been exceeded!");
        }

        WriteInt32BigEndian(nonceOrAssociatedData, nonceOrAssociatedData.Length - 4, chunkIndex);
    }

    internal static int GetCipherChunkSize(byte[] lengthPrefix, int maxCipherChunkSize)
    {
        if (lengthPrefix.Length == 0)
        {
            throw new AbpException("The encrypted BLOB is corrupted or has an invalid format: missing terminal record!");
        }

        if (lengthPrefix.Length < ChunkLengthPrefixSize)
        {
            throw new AbpException("The encrypted BLOB is corrupted or has an invalid format: truncated chunk!");
        }

        var cipherChunkSize = ReadInt32BigEndian(lengthPrefix, 0);
        if (cipherChunkSize < 0 || cipherChunkSize > maxCipherChunkSize)
        {
            throw new AbpException("The encrypted BLOB is corrupted or has an invalid format: invalid chunk length!");
        }

        return cipherChunkSize;
    }

    internal static byte[]? ReadExactly(Stream stream, int count)
    {
        var buffer = ReadUpTo(stream, count);
        return buffer.Length == count ? buffer : null;
    }

    internal static byte[] ReadUpTo(Stream stream, int count)

View on GitHub (pinned to 7ed43b1931)

Solutions

Re-upload the BLOB from a known-good source.
Verify storage-level object integrity (checksums, ETag, content-length).
Check for storage-side corruption or replication lag serving a stale partial object.
Ensure the writer and reader use the same codec version and chunk format.

Example fix

// before — reading from an unverified source
using var s = await provider.GetStreamAsync(name);
var plain = await DecryptAsync(s); // throws [89]

// after — verify length first
var info = await provider.GetOrNullAsync(name);
if (info == null || info.ContentLength < MinimumCipherLength)
    throw new InvalidOperationException("corrupt or truncated blob");

Defensive patterns

Strategy: try-catch

Validate before calling

// Reject objects whose length cannot contain even one length prefix.
var info = await provider.GetOrNullAsync(name);
if (info == null || info.ContentLength < 4 /* ChunkLengthPrefixSize */)
    throw new InvalidOperationException($"BLOB '{name}' is too short to contain a valid chunk header.");

Type guard

public sealed record MinLengthBlob(string Name, long ContentLength)
{
    public static MinLengthBlob Check(string name, long len)
    {
        const int MinCipherLen = 16; // magic + at least a length prefix
        if (len < MinCipherLen) throw new InvalidOperationException("blob too short");
        return new MinLengthBlob(name, len);
    }
}

Try / catch

try
{
    return await blob.GetAllBytesAsync(name);
}
catch (AbpException ex) when (ex.Message.Contains("truncated chunk"))
{
    logger.LogError(ex, "BLOB '{Name}' truncated mid-header; re-upload.", name);
    throw;
}

Prevention

Verify object content-length against expectations before decrypting.
Store ETag/checksums and validate them on read.
Re-upload truncated objects rather than retrying reads.
Match writer and reader codec versions.

When it happens

Trigger: Decrypting a BLOB where the cipher stream ends after 1–3 bytes of a length prefix instead of the full 4 (e.g. truncation in the middle of a chunk boundary).

Common situations: Truncated object in storage; partial download; byte-level corruption that altered boundaries; mismatched format version producing wrong offsets.

Related errors

AI-assisted analysis of abpframework/abp@7ed43b1931 (2026-08-13). Data as JSON: /api/errors/1e4541d2419c4639. Report an issue: GitHub.