Description

In Bouncy Castle JCE Provider version 1.55 and earlier the DSA does not fully validate ASN.1 encoding of signature on verification. It is possible to inject extra elements in the sequence making up the signature and still have it validate, which in some cases may allow the introduction of 'invisible' data into a signed structure.

Mitigation

We recommend upgrading to a version of this component that is not vulnerable to this specific issue.

Related links:

• http://web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-2016-1000338

• https://www.bouncycastle.org/releasenotes.html