The XML digital signature functionality (xsec/dsig/DSIGReference.cpp) in Apache Santuario XML Security for C++ (aka xml-security-c) before 1.7.1 allows context-dependent attackers to reuse signatures and spoof arbitrary content via crafted Reference elements in the Signature, aka "XML Signature Bypass issue."
https://www.tenable.com/security/tns-2018-15
http://www.debian.org/security/2013/dsa-2710
http://archives.neohapsis.com/archives/fulldisclosure/2013-06/0140.html