This issue can be avoided by not setting any telnet options for the curl command line tool (using the -t / --telnet-option command line option) or the libcurl library (using the CURLOPT_TELNETOPTIONS option) when telnet protocol is not meant to be used. If telnet protocol needs to be used with curl / libcurl, along with the NEW_ENV telnet option, ensure that no environment variable set via the NEW_ENV option has the name or value longer than 127 bytes.

As per upstream "The function X509_issuer_and_serial_hash() is never directly called by OpenSSL itself so applications are only vulnerable if they use this function directly and they use it on certificates that may have been obtained from untrusted sources."