Bug 35861 - RSAManaged randomly throws CryptographicException Error occurred while decoding OAEP padding.
Summary: RSAManaged randomly throws CryptographicException Error occurred while decodi...
Status: NEW
Alias: None
Product: Class Libraries
Classification: Mono
Component: Mono.Security ()
Version: 3.2.x
Hardware: PC Windows
: --- normal
Target Milestone: Untriaged
Assignee: Bugzilla
Depends on:
Reported: 2015-11-14 12:21 UTC by Andrew Arnott
Modified: 2015-11-14 12:21 UTC (History)
2 users (show)

Is this bug a regression?: ---
Last known good build:

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Description Andrew Arnott 2015-11-14 12:21:00 UTC
Given a constant RSA key and data, RSAManaged will throw intermittently. It should succeed or fail determininstically:

Failure: CryptographicException Error occurred while decoding OAEP padding.
Failure: CryptographicException Error occurred while decoding OAEP padding.
Failure: CryptographicException Error occurred while decoding OAEP padding.

This is the repro program: (I compiled and ran within VS, on the desktop CLR -- not mono)

using Mono.Security.Cryptography;
using System;
using System.Security.Cryptography;

namespace OaepPaddingBugRepro
    class Program
        static void Main(string[] args)
            int successCount = 0, failureCount = 0;
            while (successCount < 3 || failureCount < 3)
                catch (Exception ex)
                    Console.WriteLine($"Failure: {ex.GetType().Name} {ex.Message}");

        static void Test()
            var parameters = new RSAParameters
                D = Convert.FromBase64String("Gr0sTmpOMjly6e5m8/54WKCLzWbXMgS3Azt37bRjV9nFGDqoq6gbwSnB709oouNPmqc4hE/6AqEnplfBfHX7YQ=="),
                Q = Convert.FromBase64String("AGXbnimLuplWSVQ9/wE2eaISn5lF2tF1vKtvNSL3anoJ"),
                P = Convert.FromBase64String("AAGX4W2H9Y+uATS4dwnHnE6ROezx5275HLAjfARLRPQ3Ow=="),
                DP = Convert.FromBase64String("AAER6O4wbqT1epPYCQDFTt+oQVkwvnXUzwIuYjtT/NNwPw=="),
                DQ = Convert.FromBase64String("FTClLLt27GN5Cd+D53qvvznknfxcU2sM/xU5lramHhE="),
                Exponent = Convert.FromBase64String("AQAB"),
                InverseQ = Convert.FromBase64String("ACR2PamFTCPoeZEf73/OQeEVmLbd/xwozz8UOqGejqlh"),
                Modulus = Convert.FromBase64String("AKJJ2g6qhep28mB5ySYb44dk9ZE0H+JQug9Tq2/1BjebHtW+YP/1Ds3tK/rQvL1A+yhLkFWOaQD6043AwJpWDxM="),
            var rsa = new RSAManaged();

            byte[] data = new byte[] { 1, 2, 3 };
            byte[] ciphertext, plaintext;

            var keyExchange = new RSAOAEPKeyExchangeFormatter(rsa);
            ciphertext = keyExchange.CreateKeyExchange(data);

            var keyExchange2 = new RSAOAEPKeyExchangeDeformatter(rsa);
            plaintext = keyExchange2.DecryptKeyExchange(ciphertext);