Database error servicing email when decrypting PGP Messages from a specific sender

Gateway
1

Hello,
we are using CipherMail Community edition to decrypt PGP Messages in front of our E-Mail Server. That works great but now we got a new communication Partner who sends his invoices via PGP Encryption. When processing these Messages I get an Error “Database error servicing email” and the Mail goes thru unencrypted. The following Lines are in the log:

06 Jan 2023 02:41:59 | INFO incoming; MailID: d9a27da3-b160-49f0-a469-2bfc340e4483; Recipients: [recpient(at)domain(dot)de]; Originator: sender(at)domain(dot)de; Sender: sender(at)domain(dot)de; Remote address: x.x.x.x; Subject: Ihre Absender Rechnung Nr.: 6454949049; Message-ID: <20230106024135.605CC208B8(at)EBIB-PROD.domain(dot)de>; (mitm.application.djigzo.james.mailets.Log) [Spool Thread #1]
06 Jan 2023 02:41:59 | INFO Filtering subject; MailID: d9a27da3-b160-49f0-a469-2bfc340e4483; Recipients: [recpient(at)domain(dot)de] (mitm.application.djigzo.james.mailets.Default) [Spool Thread #1]
06 Jan 2023 02:41:59 | INFO Subject filtered; MailID: d9a27da3-b160-49f0-a469-2bfc340e4483; Recipients: [recpient(at)domain(dot)de]; Originator: sender(at)domain(dot)de; Sender: sender(at)domain(dot)de; Remote address: x.x.x.x; Subject: Ihre Absender Rechnung Nr.: 6454949049; Message-ID: <20230106024135.605CC208B8(at)EBIB-PROD.domain(dot)de>; (mitm.application.djigzo.james.mailets.Log) [Spool Thread #1]
06 Jan 2023 02:41:59 | INFO To internal recipient(s); MailID: d9a27da3-b160-49f0-a469-2bfc340e4483; Recipients: [recpient(at)domain(dot)de] (mitm.application.djigzo.james.mailets.Default) [Spool Thread #1]
06 Jan 2023 02:41:59 | INFO “add security info” is enabled for the recipient(s); MailID: d9a27da3-b160-49f0-a469-2bfc340e4483; Recipients: [recpient(at)domain(dot)de] (mitm.application.djigzo.james.mailets.Default) [Spool Thread #1]
06 Jan 2023 02:41:59 | ERROR Database error servicing email. (mitm.application.djigzo.james.mailets.PGPHandler) [Spool Thread #1]
mitm.common.hibernate.DatabaseException: javax.mail.internet.ParseException: Expected MIME type, got ;
at mitm.application.djigzo.james.mailets.AbstractTransactedMailet$1.doAction(AbstractTransactedMailet.java:143) ~[ciphermail-core.jar:5.4.1.0gd59d06760]
at mitm.common.hibernate.DatabaseActionExecutorImpl$1.doAction(DatabaseActionExecutorImpl.java:164) ~[ciphermail-core.jar:5.4.1.0gd59d06760]
at mitm.common.hibernate.DatabaseActionExecutorImpl.executeTransaction(DatabaseActionExecutorImpl.java:81) ~[ciphermail-core.jar:5.4.1.0gd59d06760]
at mitm.common.hibernate.DatabaseActionExecutorImpl.executeTransaction(DatabaseActionExecutorImpl.java:158) ~[ciphermail-core.jar:5.4.1.0gd59d06760]
at mitm.application.djigzo.james.mailets.AbstractTransactedMailet.serviceMail(AbstractTransactedMailet.java:125) [ciphermail-core.jar:5.4.1.0gd59d06760]
at mitm.application.djigzo.james.mailets.AbstractDjigzoMailet.service(AbstractDjigzoMailet.java:281) [ciphermail-core.jar:5.4.1.0gd59d06760]
at org.apache.james.transport.LinearProcessor.service(LinearProcessor.java:424) [james-2.3.1.jar:?]
at org.apache.james.transport.JamesSpoolManager.process(JamesSpoolManager.java:405) [james-2.3.1.jar:?]
at org.apache.james.transport.JamesSpoolManager.run(JamesSpoolManager.java:309) [james-2.3.1.jar:?]
at java.lang.Thread.run(Thread.java:829) [?:?]
Caused by: javax.mail.internet.ParseException: Expected MIME type, got ;
at javax.mail.internet.ContentType.(ContentType.java:95) ~[mail.jar:1.4.5-SNAPSHOT]
at javax.mail.internet.MimeBodyPart.updateHeaders(MimeBodyPart.java:1322) ~[mail.jar:1.4.5-SNAPSHOT]
at javax.mail.internet.MimeBodyPart.updateHeaders(MimeBodyPart.java:1021) ~[mail.jar:1.4.5-SNAPSHOT]
at javax.mail.internet.MimeMultipart.updateHeaders(MimeMultipart.java:419) ~[mail.jar:1.4.5-SNAPSHOT]
at javax.mail.internet.MimeBodyPart.updateHeaders(MimeBodyPart.java:1345) ~[mail.jar:1.4.5-SNAPSHOT]
at javax.mail.internet.MimeMessage.updateHeaders(MimeMessage.java:2107) ~[mail.jar:1.4.5-SNAPSHOT]
at javax.mail.internet.MimeMessage.saveChanges(MimeMessage.java:2075) ~[mail.jar:1.4.5-SNAPSHOT]
at mitm.common.security.openpgp.PGPMIMEHandler.createNewMessageFromMIME(PGPMIMEHandler.java:663) ~[ciphermail-core.jar:5.4.1.0gd59d06760]
at mitm.common.security.openpgp.PGPMIMEHandler.handlePGPMIMEEncrypted(PGPMIMEHandler.java:713) ~[ciphermail-core.jar:5.4.1.0gd59d06760]
at mitm.common.security.openpgp.PGPMIMEHandler.handleMessage(PGPMIMEHandler.java:270) ~[ciphermail-core.jar:5.4.1.0gd59d06760]
at mitm.common.security.openpgp.PGPRecursiveValidatingMIMEHandler.handleMessage(PGPRecursiveValidatingMIMEHandler.java:1125) ~[ciphermail-core.jar:5.4.1.0gd59d06760]
at mitm.common.security.openpgp.PGPRecursiveValidatingMIMEHandler.handleMessage(PGPRecursiveValidatingMIMEHandler.java:1102) ~[ciphermail-core.jar:5.4.1.0gd59d06760]
at mitm.application.djigzo.james.mailets.PGPHandler.serviceMailTransacted(PGPHandler.java:498) ~[ciphermail-core.jar:5.4.1.0gd59d06760]
at mitm.application.djigzo.james.mailets.AbstractTransactedMailet$1.doAction(AbstractTransactedMailet.java:140) ~[ciphermail-core.jar:5.4.1.0gd59d06760]
… 9 more
06 Jan 2023 02:41:59 | INFO Message handling is finished. Sending to final recipient(s); MailID: d9a27da3-b160-49f0-a469-2bfc340e4483; Recipients: [recpient(at)domain(dot)de]; Originator: sender(at)domain(dot)de; Sender: sender(at)domain(dot)de; Remote address: x.x.x.x; Subject: Ihre Absender Rechnung Nr.: 6454949049; Message-ID: <20230106024135.605CC208B8(at)EBIB-PROD.domain(dot)de>; (mitm.application.djigzo.james.mailets.Log) [Spool Thread #1]

The Mail arrives in outlook with an Attachment “PGP-MIME version identification” and another Attachment “encrypted.asc”. I can decrypt this attachment with OpenPGP, it decrypts to a file “encrypted”, which I rename to “encrypted.eml”, bring it back to Outlook and I have the decrypted Message. The Beginning of this decrypted Message looks like

MIME-Version: 1.0
To: <recpient(at)domain(dot)de>
From: <No-Reply(at)domain(dot)de>
Subject: =?ISO-8859-1?obfuscated
Reply-To: <No-Reply(at)domain(dot)de>
Content-Type: multipart/mixed; boundary=“7HK07gdNP5GA63UuZuxTdpEqyljga1agpxPKMU2p”
–7HK07gdNP5GA63UuZuxTdpEqyljga1agpxPKMU2p
Content-Type: text/plain; charset=“iso-8859-15”
Guten Tag,
anbei ¸bermitteln wir Ihre aktuelle Rechnung.
Mit freundlichen Gr¸flen
Ihre Absender
–7HK07gdNP5GA63UuZuxTdpEqyljga1agpxPKMU2p
Content-Type: ;name=“B_5023482686_25_01.6454949048.pdf”
Content-Transfer-Encoding: base64
Content-Disposition: attachment;filename=“B_5023482686_25_01.6454949048.pdf”
JVBERi0xLjMNCiXi48/TDQolUlNUWFBERjMgUGFyYW1ldGVyczoNCjIgMCBvYmoNCjw8DQovVHlw
ZSAvRm9udERlc2NyaXB0b3INCi9Bc2NlbnQgNzIwDQovQ2FwSGVpZ2h0IDY2MA0KL0Rlc2NlbnQg

I yesterday Upgraded CipherMail to Version: 5.4.1.0gd59d06760 but the error still comes. As other Mails are decrypted/encrypted as they should be, I suspect the problem is caused by how the sender encrypts the mails. “Enable PGP/INLINE to internal” is enabled for this User, but doesn’t change the behaviour.

Any Help much appreciated,
Christian

2

Content-Type: ;name=“B_5023482686_25_01.6454949048.pdf”

This looks like an invalid Content-Type because the actual type is missing.

Is this the Content-Type of the decrypted part? Or is this a typo?

3

Hi Martijn,

thank you for your fast reply. This is the actual content type they send, this line was not obfuscated by me. That would match to the error line

Expected MIME type, got ;

right? Can I do something to solve it?

Christian

4

I don’t think there is an easy solution. The Content-Type is invalid. I think javamail, which is responsible for MIME handling, supports some cleanup functionality but this requires additional Java code.

5

Hi Martijn,
thank you really for pointing me in the right direction, I haven’t seen this fact in the logs. I’m now able to tell the Partner that the initial E-Mail that is encrypted in the PGP Envelope should have

Content-type: application/pdf; name=“B_5023482686_25_01.6454949048.pdf”;

Instead of

Content-Type: ;name=“B_5023482686_25_01.6454949048.pdf”

So I can tell them (and our users), it is their fault and they have to correct it.
Again, thank you for your help.

Christian