Azure Key Vault
An Azure service that is used to manage and protect cryptographic keys and other secrets used by cloud apps and services.
1,368 questions
Azure Key Vault Encrypt with AES returns 413 Request Entity Too Large
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Bobby Bridges
0
Reputation points
I'm using a 256 bit AES key that's stored in Azure Managed HSM and I'm trying to encrypt data using the Azure SDK. When I try to encrypt the data using the AES key, the SDK returns a 413 Request Entity Too Large error. The data is likely in JSON format and I'm using Encoding.UTF8.GetBytes prior to making the Encrypt call with the SDK. Do you have any suggestions to avoid this error?
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Akhilesh Vallamkonda 11,680 Reputation points Microsoft Vendor2025-02-04T21:17:11.93+00:00 Thank you for posting Microsoft Q&A Forum!
The 413 Request Entity Too Large error typically occurs when the size of the data being sent exceeds the maximum allowed limit.
Sign and verify operations algorithms must match the key type, otherwise service will return key size is incorrect error.
Ensure that the size of the secret, certificate, or key you're trying to upload is within the allowed limits. Azure Key Vault has specific size limits for different types of entities.
could you please verify Key types, algorithms, and operations. and Azure Key Vault service limits is compatible. -
Bobby Bridges 0 Reputation points
2025-02-05T12:07:30.5+00:00 @Akhilesh Vallamkonda does this mean the data to be encrypted has to be less than 4KB in size?
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Akhilesh Vallamkonda 11,680 Reputation points Microsoft Vendor
2025-02-05T20:35:35.1133333+00:00 Hi @Bobby Bridges
May I know the size of the JSON data you are using, could you please send us the JSON data file to azcommunity [at] microsoft [dot] com referencing this issue with a subject line "ATTN:akhilesh" -
Bobby Bridges 0 Reputation points
2025-02-06T12:41:38.3666667+00:00 @Akhilesh Vallamkonda the sizes of the data that is failing ranges from 24KB to 82KB. I sent an email reply with a sample of the JSON data that is failing.
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Akhilesh Vallamkonda 11,680 Reputation points Microsoft Vendor
2025-02-06T22:51:09.9233333+00:00 Hi @Bobby Bridges
I am checking this and will get back to you with further inputs.
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