"During certificate verification, OpenSSL (starting from version 1.0.1n and
1.0.2b) will attempt to find an alternative certificate chain if the first
attempt to build such a chain fails. An error in the implementation of this
logic can mean that an attacker could cause certain checks on untrusted
certificates to be bypassed, such as the CA flag, enabling them to use a valid
leaf certificate to act as a CA and "issue" an invalid certificate.
"This issue will impact any application that verifies certificates including
SSL/TLS/DTLS clients and SSL/TLS/DTLS servers using client authentication.
"This issue affects OpenSSL versions 1.0.2c, 1.0.2b, 1.0.1n and 1.0.1o.
"OpenSSL 1.0.2b/1.0.2c users should upgrade to 1.0.2d
"OpenSSL 1.0.1n/1.0.1o users should upgrade to 1.0.1p"
Source: https://www.openssl.org/news/secadv_20150709.txt
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"Move fast and break things," out. "Move carefully and fix what you break," in.
