The html package (aka x/net/html) through 2018-09-17 in Go mishandles <math><template><mo><template>, leading to a "panic: runtime error" in parseCurrentToken in parse.go during an html.Parse call.

The html package (aka x/net/html) before 2018-07-13 in Go mishandles "in frameset" insertion mode, leading to a "panic: runtime error" for html.Parse of <template><object>, <template><applet>, or <template><marquee>. This is related to HTMLTreeBuilder.cpp in WebKit.

The "go get" implementation in Go 1.9.4, when the -insecure command-line option is used, does not validate the import path (get/vcs.go only checks for "://" anywhere in the string), which allows remote attackers to execute arbitrary OS commands via a crafted web site.

Go before 1.8.7, Go 1.9.x before 1.9.4, and Go 1.10 pre-releases before Go 1.10rc2 allow "go get" remote command execution during source code build, by leveraging the gcc or clang plugin feature, because -fplugin= and -plugin= arguments were not blocked.

The net/http library in net/http/transfer.go in Go before 1.4.3 does not properly parse HTTP headers, which allows remote attackers to conduct HTTP request smuggling attacks via a request with two Content-length headers.

The net/http library in net/textproto/reader.go in Go before 1.4.3 does not properly parse HTTP header keys, which allows remote attackers to conduct HTTP request smuggling attacks via a space instead of a hyphen, as demonstrated by "Content Length" instead of "Content-Length."

Go before 1.8.4 and 1.9.x before 1.9.1 allows "go get" remote command execution. Using custom domains, it is possible to arrange things so that example.com/pkg1 points to a Subversion repository but example.com/pkg1/pkg2 points to a Git repository. If the Subversion repository includes a Git checkout in its pkg2 directory and some other work is done to ensure the proper ordering of operations, "go get" can be tricked into reusing this Git checkout for the fetch of code from pkg2. If the Subversion repository's Git checkout has malicious commands in .git/hooks/, they will execute on the system running "go get."

An unintended cleartext issue exists in Go before 1.8.4 and 1.9.x before 1.9.1. RFC 4954 requires that, during SMTP, the PLAIN auth scheme must only be used on network connections secured with TLS. The original implementation of smtp.PlainAuth in Go 1.0 enforced this requirement, and it was documented to do so. In 2013, upstream issue #5184, this was changed so that the server may decide whether PLAIN is acceptable. The result is that if you set up a man-in-the-middle SMTP server that doesn't advertise STARTTLS and does advertise that PLAIN auth is OK, the smtp.PlainAuth implementation sends the username and password.

On Darwin, user's trust preferences for root certificates were not honored. If the user had a root certificate loaded in their Keychain that was explicitly not trusted, a Go program would still verify a connection using that root certificate.

The net/http package's Request.ParseMultipartForm method starts writing to temporary files once the request body size surpasses the given "maxMemory" limit. It was possible for an attacker to generate a multipart request crafted such that the server ran out of file descriptors.