Summary
The remote host is missing an update to gnupg
announced via advisory DSA 010-1.
Solution
https://secure1.securityspace.com/smysecure/catid.html?in=DSA%20010-1
Insight
Two bugs in GnuPG have recently been found:
1. false positives when verifying detached signatures - -----------------------------------------------------
There is a problem in the way gpg checks detached signatures which can lead to false positives. Detached signature can be verified with a command like this:
gpg --verify detached.sig < mydata
If someone replaced detached.sig with a signed text (ie not a detached signature) and then modified mydata gpg would still report a successfully verified signature.
To fix the way the --verify option works has been changes: it now needs two options when verifying detached signatures: both the file with the detached signature, and the file with the data to be verified. Please note that this makes it incompatible with older versions!
2. secret keys are silently imported
- ------------------------------------
Florian Weimer discovered that gpg would import secret keys from key-servers. Since gpg considers public keys corresponding to known secret keys to be ultimately trusted an attacked can use this circumvent the web of trust.
To fix this a new option was added to to tell gpg it is allowed to import secret keys: --allow-key-import.
Both these fixes are in version 1.0.4-1.1 and we recommend that you upgrade your gnupg package immediately.