CVE-2023-24539 Improper sanitization of CSS values in html/template
Attackers can inject unexpected HTML via CSS contexts in Go templates, potentially leading to cross-site scripting or code execution.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2023-24539?
CVE-2023-24539 is a high-severity cross-site scripting vulnerability in Golang Go, published on 11 May 2023. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
Angle brackets (<>) are not considered dangerous characters when inserted into CSS contexts. Templates containing multiple actions separated by a '/' character can result in unexpectedly closing the CSS context and allowing for injection of unexpected HTML, if executed with untrusted input.
Which versions are affected by CVE-2023-24539?
2 open source packages ship an affected version, including golang and stdlib. It affects 1 product.
| Package | Affected | Fixed in |
|---|---|---|
golang Bitnami | All versions | 1.19.9, 1.20.4 |
stdlib Go | All versions | 1.19.9, 1.20.4 |
Products include Golang Go.
How do I fix CVE-2023-24539?
Upgrade golang to a fixed version for your release line: 1.19.9 or 1.20.4.
Escape output for the context it lands in and set a strict Content Security Policy. Upgrading the affected component is the real fix. More about Cross-site scripting.
Is CVE-2023-24539 being exploited?
There is no known exploitation of CVE-2023-24539 in the wild and no public exploit code.
Other vulnerabilities in Golang Go
- CVE-2020-0601 Microsoft Windows CryptoAPI Spoofing
- CVE-2026-27143 Missing bound checks can lead to memory corruption in safe Go in cmd/compile
- CVE-2024-24790 Unexpected behavior from Is methods for IPv4-mapped IPv6 addresses in net/netip
- CVE-2023-39320 Arbitrary code execution via go.mod toolchain directive in cmd/go
- CVE-2023-24540 Improper handling of JavaScript whitespace in html/template
Sources
Also known as AZL-26614, AZL-26625, AZL-37307, AZL-37362, AZL-52668, AZL-79046 and 6 more.