[security] Go 1.21.1 and Go 1.20.8 are released

[Cherry Mui]

Hello gophers,

We have just released Go versions 1.21.1 and 1.20.8, minor point releases.

These minor releases include 4 security fixes following the security policy:

• cmd/go: go.mod toolchain directive allows arbitrary execution
  
  The go.mod toolchain directive, introduced in Go 1.21, could be leveraged to
  execute scripts and binaries relative to the root of the module when the "go"
  command was executed within the module. This applies to modules downloaded using
  the "go" command from the module proxy, as well as modules downloaded directly
  using VCS software.
  
  Thanks to Juho Nurminen of Mattermost for reporting this issue.
  
  This is CVE-2023-39320 and Go issue https://go.dev/issue/62198.
  
  

• html/template: improper handling of HTML-like comments within script contexts

The html/template package did not properly handle HMTL-like "<!--" and "-->"

comment tokens, nor hashbang "#!" comment tokens, in <script> contexts. This may

cause the template parser to improperly interpret the contents of <script>

contexts, causing actions to be improperly escaped. This could be leveraged to

perform an XSS attack.

Thanks to Takeshi Kaneko (GMO Cybersecurity by Ierae, Inc.) for reporting this
issue.

This is CVE-2023-39318 and Go issue https://go.dev/issue/62196.

• html/template: improper handling of special tags within script contexts

The html/template package did not apply the proper rules for handling occurrences

of "<script", "<!--", and "</script" within JS literals in <script> contexts.

This may cause the template parser to improperly consider script contexts to be

terminated early, causing actions to be improperly escaped. This could be

leveraged to perform an XSS attack.

Thanks to Takeshi Kaneko (GMO Cybersecurity by Ierae, Inc.) for reporting this

issue.

This is CVE-2023-39319 and Go issue https://go.dev/issue/62197.

• crypto/tls: panic when processing post-handshake message on QUIC connections
  
  Processing an incomplete post-handshake message for a QUIC connection caused a panic.
  
  Thanks to Marten Seemann for reporting this issue.
  
  This is CVE-2023-39321 and CVE-2023-39322 and Go issue https://go.dev/issue/62266.

View the release notes for more information:

https://go.dev/doc/devel/release#go1.21.1

You can download binary and source distributions from the Go website:

https://go.dev/dl/

To compile from source using a Git clone, update to the release with

git checkout go1.21.1 and build as usual.

We have also released Go version 1.19.13, a minor point release that

only includes fixes to improve its forward and backward compatibility.

Thanks to everyone who contributed to the releases.

Cheers,

Cherry, Joedian, and Dmitri for the Go team