CVE-2023-29453 Agent 2 package are built with Go version affected by CVE-2023-24538

Critical 9.8 Published 12 Oct 2023 Updated 18 Sep 2024

Attackers can inject arbitrary JavaScript into Go templates via backticks, potentially leading to code execution in Zabbix deployments.

Exploited in the wild: Not known
Login needed: Not needed
Attackable: Over the internet
Victim action needed: Not needed
Fix: Available

What is CVE-2023-29453?

CVE-2023-29453 is a critical code injection vulnerability in Zabbix, published on 12 Oct 2023. An attacker can exploit it over the internet without logging in, with no action from the victim.

Official description

Templates do not properly consider backticks (`) as Javascript string delimiters, and do not escape them as expected. Backticks are used, since ES6, for JS template literals. If a template contains a Go template action within a Javascript template literal, the contents of the action can be used to terminate the literal, injecting arbitrary Javascript code into the Go template. As ES6 template literals are rather complex, and themselves can do string interpolation, the decision was made to simply disallow Go template actions from being used inside of them (e.g., "var a = {{.}}"), since there is no obviously safe way to allow this behavior. This takes the same approach as github.com/google/safehtml. With fix, Template. Parse returns an Error when it encounters templates like this, with an ErrorCode of value 12. This ErrorCode is currently unexported but will be exported in the release of Go 1.21. Users who rely on the previous behavior can re-enable it using the GODEBUG flag jstmpllitinterp=1, with the caveat that backticks will now be escaped. This should be used with caution.

Weakness: CWE-94

Which versions are affected by CVE-2023-29453?

It affects 1 product.

Products include Zabbix Zabbix-Agent2.

How do I fix CVE-2023-29453?

Upgrade to a fixed version.

Upgrade, and never evaluate templates, expressions or code built from user input. More about Code injection.

Is CVE-2023-29453 being exploited?

There is no known exploitation of CVE-2023-29453 in the wild and no public exploit code.

Sources

Also known as DEBIAN-CVE-2023-29453, GHSA-7374-hfgm-rm8v, UBUNTU-CVE-2023-29453.