Vulnerability Note VU#566640

pgp4pine fails to properly check for expired public keys

Original Release date: 12 Jul 2001 | Last revised: 15 Jan 2002


The program pgp4pine version 1.75.6 fails to properly identify expired keys when working with the Gnu Privacy Guard program (GnuPG). This failure may result in the clear-text transmission of senstive information when used with the PINE mail reading package.


The program pgp4pine provides an interface for various PGP implementations to the PINE mail reading package. Version 1.75.6 of pgp4pine does not check to see if public keys are expired when loading keys from the GnuPG openPGP implementation. When a user specifies an expired public key in their key ring and attempts to encrypt a message with that expired public key, pgp4pine will not check to see if the key is expired. Instead, pgp4pine will issue a command to GnuPG to encrypt the email message with the expired key. The encryption will not be successful and GnuPG will return an error message indicating that the key is invalid. pgp4pine does not detect the error message, and does not notify the user that an error has occurred. The clear text is then returned to the program flow control of PINE. PINE will then transmit the message in clear text.

For more information, see the advisory provided by CryptNET.


Sensitive materials may be transmitted over the network in clear text, without the intention or knowledge of the sender.


No vender patch is known to exist. However, a patch is provided by CryptNET.

Validate all keys on your keyring at regular intervals. Remove expired keys.

Systems Affected (Learn More)

VendorStatusDate NotifiedDate Updated
Holger LammAffected25 Jun 200112 Jul 2001
If you are a vendor and your product is affected, let us know.

CVSS Metrics (Learn More)

Group Score Vector
Base N/A N/A
Temporal N/A N/A
Environmental N/A N/A



Our thanks to CryptNET , who published an advisory on this problem, available at

This document was written by Jason Rafail.

Other Information

  • CVE IDs: CAN-2001-0273
  • Date Public: 20 Feb 2001
  • Date First Published: 12 Jul 2001
  • Date Last Updated: 15 Jan 2002
  • Severity Metric: 0.68
  • Document Revision: 9


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