Parsing arbitrary HTML which is then rendered using Render can result in an unexpected HTML tree. This can be leveraged to execute XSS attacks in applications that attempt to sanitize input HTML before rendering.

Parsing arbitrary HTML which is then rendered using Render can result in an unexpected HTML tree. This can be leveraged to execute XSS attacks in applications that attempt to sanitize input HTML before rendering.

Parsing arbitrary HTML can consume excessive CPU time, possibly leading to denial of service.

Parsing arbitrary HTML which is then rendered using Render can result in an unexpected HTML tree. This can be leveraged to execute XSS attacks in applications that attempt to sanitize input HTML before rendering.

The ToASCII and ToUnicode functions incorrectly accept Punycode-encoded labels that decode to an ASCII-only label. For example, ToUnicode("xn--example-.com") incorrectly returns the name "example.com" rather than an error. This behavior can lead to privilege escalation in programs using the idna package. For example, a program which performs privilege checks on the ASCII hostname may reject "example.com" but permit "xn--example-.com". If that program subsequently converts the ASCII hostname to Unicode, it will inadvertently permits access to the Unicode name "example.com".

Parsing arbitrary HTML which is then rendered using Render can result in an unexpected HTML tree. This can be leveraged to execute XSS attacks in applications that attempt to sanitize input HTML before rendering.

When using LookupCNAME with the cgo DNS resolver, a very long CNAME response can trigger a double-free of C memory and a crash.

The Dial and LookupPort functions panic on Windows when provided with an input containing a NUL (0).

A malformed DNS message in response to a query can cause the Lookup functions to get stuck in an infinite loop.

The html package (aka x/net/html) through 2018-09-25 in Go mishandles <table><math><select><mi><select></table>, leading to an infinite loop during an html.Parse call because inSelectIM and inSelectInTableIM do not comply with a specification.

The html package (aka x/net/html) through 2018-09-25 in Go mishandles <svg><template><desc><t><svg></template>, leading to a "panic: runtime error" (index out of range) in (*nodeStack).pop in node.go, called from (*parser).clearActiveFormattingElements, during an html.Parse call.

The html package (aka x/net/html) through 2018-09-25 in Go mishandles <math><template><mn><b></template>, leading to a "panic: runtime error" (index out of range) in (*insertionModeStack).pop in node.go, called from inHeadIM, during an html.Parse call.

The html package (aka x/net/html) through 2018-09-17 in Go mishandles <template><tBody><isindex/action=0>, leading to a "panic: runtime error" in inBodyIM in parse.go during an html.Parse call.

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.