Add test to reproduce the problem

backend/bdd/features/pki/acme/account.feature

@@ -11,8 +11,27 @@ Feature: Account
     When I have an ACME client connecting to "{BASE_URL}/api/v1/pki/acme/profiles/{acme_profile.id}/directory"
     Then I register a new ACME account with email fangpen@infisical.com and EAB key id "{acme_profile.eab_kid}" with secret "{acme_profile.eab_secret}" as acme_account
     And I memorize acme_account.uri as account_uri
-    And I find the existing ACME account with email fangpen@infisical.com and EAB key id "{acme_profile.eab_kid}" with secret "{acme_profile.eab_secret}" as acme_account
+    And I find the existing ACME account with email fangpen@infisical.com and EAB key id "{acme_profile.eab_kid}" with secret "{acme_profile.eab_secret}" as retrieved_account
-    And the value acme_account.uri should be equal to "{account_uri}"
+    And the value retrieved_account.uri should be equal to "{account_uri}"
+
+  # Note: This is a very special case for cert-manager.
+  # There's a bug in their ACME client implementation, they don't take the account KID value they have
+  # and relying on a '{"onlyReturnExisting": true}' new-account request to find out their KID value.
+  # But the problem is, that new-account request doesn't come with EAB. And while the get existing account operation
+  # fails, they just discard the error and proceed to request a new order. Since no KID provided, their ACME
+  # client will send JWK instead. As a result, we are seeing KID not provide in header error for the new-order
+  # endpoint.
+  #
+  # To solve the problem, we lose the check for EAB a bit for the onlyReturnExisting new account request
+  # ref: https://github.com/cert-manager/cert-manager/issues/7388#issuecomment-3535630925
+  Scenario: Create a new account with EAB then retrieve it without EAB
+    Given I have an ACME cert profile as "acme_profile"
+    When I have an ACME client connecting to "{BASE_URL}/api/v1/pki/acme/profiles/{acme_profile.id}/directory"
+    Then I register a new ACME account with email fangpen@infisical.com and EAB key id "{acme_profile.eab_kid}" with secret "{acme_profile.eab_secret}" as acme_account
+    And I memorize acme_account.uri as account_uri
+    And I find the existing ACME account without EAB as retrieved_account
+    And the value error with should be absent
+    And the value retrieved_account.uri should be equal to "{account_uri}"
 
   Scenario: Create a new account without EAB
     Given I have an ACME cert profile as "acme_profile"

backend/bdd/features/steps/pki_acme.py

@@ -434,6 +434,20 @@ def step_impl(context: Context, email: str, kid: str, secret: str, account_var:
     )
 
 
+@then("I find the existing ACME account without EAB as {account_var}")
+def step_impl(context: Context, account_var: str):
+    acme_client = context.acme_client
+    registration = messages.NewRegistration.from_data(
+        only_return_existing=True,
+    )
+    # Reset account so that it will send JWK instead of KID
+    acme_client.net.account = None
+    try:
+        context.vars[account_var] = acme_client.new_account(registration)
+    except Exception as exp:
+        context.vars["error"] = exp
+
+
 @then("I register a new ACME account with email {email} without EAB")
 def step_impl(context: Context, email: str):
     acme_client = context.acme_client
@@ -600,6 +614,19 @@ def step_impl(context: Context, var_path: str, jq_query: str):
     )
 
 
+@then("the value {var_path} with should be absent")
+def step_impl(context: Context, var_path: str):
+    try:
+        value = eval_var(context, var_path)
+    except Exception as exp:
+        if isinstance(exp, KeyError):
+            return
+        raise
+    assert False, (
+        f"value at {var_path!r} should be absent, but we got this instead: {value!r}"
+    )
+
+
 @then('the value {var_path} with jq "{jq_query}" should be equal to {expected}')
 def step_impl(context: Context, var_path: str, jq_query: str, expected: str):
     value, result = apply_value_with_jq(