diff --git a/ledger/ledger-api-common/src/main/scala/com/digitalasset/ledger/api/tls/DecryptionParameters.scala b/ledger/ledger-api-common/src/main/scala/com/digitalasset/ledger/api/tls/DecryptionParameters.scala
index 098b69a88050..c4b0f4ee49af 100644
--- a/ledger/ledger-api-common/src/main/scala/com/digitalasset/ledger/api/tls/DecryptionParameters.scala
+++ b/ledger/ledger-api-common/src/main/scala/com/digitalasset/ledger/api/tls/DecryptionParameters.scala
@@ -8,12 +8,12 @@ import java.nio.charset.StandardCharsets
 import java.nio.file.Files
 import javax.crypto.Cipher
 import javax.crypto.spec.{IvParameterSpec, SecretKeySpec}
-
 import org.apache.commons.codec.binary.Hex
 import org.apache.commons.io.IOUtils
 import spray.json.{DefaultJsonProtocol, RootJsonFormat}
 
-import scala.util.Using
+import java.util.Base64
+import scala.util.{Try, Using}
 
 final class PrivateKeyDecryptionException(cause: Throwable) extends Exception(cause)
 
@@ -39,6 +39,15 @@ case class DecryptionParameters(
     transformation.split("/")(0)
   }
 
+  private def decodeBase64OrGetVerbatim(encrypted: Array[Byte]): Array[Byte] = {
+    val potentialBase64Char =
+      "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz/+=\n\r".getBytes()
+    encrypted.find(!potentialBase64Char.contains(_)) match {
+      case None => Try(Base64.getMimeDecoder.decode(encrypted)).getOrElse(encrypted)
+      case _ => encrypted
+    }
+  }
+
   private[tls] def decrypt(encrypted: Array[Byte]): Array[Byte] = {
     val key: Array[Byte] = Hex.decodeHex(keyInHex)
     val secretKey = new SecretKeySpec(key, algorithm)
@@ -46,7 +55,8 @@ case class DecryptionParameters(
     val cipher = Cipher.getInstance(transformation)
     val ivParameterSpec = new IvParameterSpec(iv)
     cipher.init(Cipher.DECRYPT_MODE, secretKey, ivParameterSpec)
-    cipher.doFinal(encrypted)
+    val binary = decodeBase64OrGetVerbatim(encrypted)
+    cipher.doFinal(binary)
   }
 }
 
diff --git a/ledger/ledger-api-common/src/test/suite/scala/com/digitalasset/ledger/api/tls/DecryptionParametersTest.scala b/ledger/ledger-api-common/src/test/suite/scala/com/digitalasset/ledger/api/tls/DecryptionParametersTest.scala
index b64446432fe0..fc5b5aa1c6b1 100644
--- a/ledger/ledger-api-common/src/test/suite/scala/com/digitalasset/ledger/api/tls/DecryptionParametersTest.scala
+++ b/ledger/ledger-api-common/src/test/suite/scala/com/digitalasset/ledger/api/tls/DecryptionParametersTest.scala
@@ -6,18 +6,19 @@ package com.daml.ledger.api.tls
 import java.io.ByteArrayInputStream
 import java.nio.file.Files
 import javax.crypto.{Cipher, KeyGenerator, SecretKey}
-
 import org.apache.commons.codec.binary.Hex
 import org.scalatest.matchers.should.Matchers
 import org.scalatest.wordspec.AnyWordSpec
 
+import java.util.Base64
+
 class DecryptionParametersTest extends AnyWordSpec with Matchers {
 
   "decryption parameters" should {
 
     // given
     val key: SecretKey = KeyGenerator.getInstance("AES").generateKey()
-    val clearText = "clearText123"
+    val clearText = "clearText123 " * 10
     val clearTextBytes = clearText.getBytes
     val transformation = "AES/CBC/PKCS5Padding"
     val cipher = Cipher.getInstance(transformation)
@@ -41,11 +42,20 @@ class DecryptionParametersTest extends AnyWordSpec with Matchers {
       new String(actual) shouldBe clearText
     }
 
-    "decrypt a file" in {
+    "decrypt a file" in
+      testFileDecoding("-verbatim", cipherText)
+
+    "decrypt a file in base64" in
+      testFileDecoding("-base64", Base64.getEncoder.encode(cipherText))
+
+    "decrypt a file in MIME base64" in
+      testFileDecoding("-mime-base64", Base64.getMimeEncoder.encode(cipherText))
+
+    def testFileDecoding(fileSuffix: String, content: Array[Byte]) = {
       // given
-      val tmpFilePath = Files.createTempFile("cipher-text", ".enc")
-      Files.write(tmpFilePath, cipherText)
-      assume(Files.readAllBytes(tmpFilePath) sameElements cipherText)
+      val tmpFilePath = Files.createTempFile(s"cipher-text$fileSuffix", ".enc")
+      Files.write(tmpFilePath, content)
+      assume(Files.readAllBytes(tmpFilePath) sameElements content)
 
       // when
       val actual: Array[Byte] = tested.decrypt(tmpFilePath.toFile)
diff --git a/ledger/test-common/test-certificates/BUILD.bazel b/ledger/test-common/test-certificates/BUILD.bazel
index 0d87db30fe04..05ea9dee7aee 100644
--- a/ledger/test-common/test-certificates/BUILD.bazel
+++ b/ledger/test-common/test-certificates/BUILD.bazel
@@ -80,7 +80,7 @@ chmod 444 $(location server.crt)
 
 # Encrypt server's key and dump encryption parameters to a JSON file.
 # NOTE: Encryption details used to encrypt the private must be kept in sync with `ledger/test-common/files/server-pem-decryption-parameters.json`
-$(location @openssl_dev_env//:openssl) enc -aes-128-cbc \
+$(location @openssl_dev_env//:openssl) enc -aes-128-cbc -base64 \
     -in $(location server.pem) \
     -out $(location server.pem.enc) \
     -K 0034567890abcdef1234567890abcdef \