# CVE-2023-24538: Backticks not treated as string delimiters in html/template

> Attackers can inject arbitrary JavaScript into Go templates by exploiting improper handling of backticks in JavaScript template literals.

- **Severity:** Critical 9.8 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 6 Apr 2023
- **Updated:** 13 Feb 2025
- **Also known as:** AZL-25992, AZL-25993, AZL-34751, AZL-37296, AZL-37411, AZL-78990, AZL-98649, BIT-golang-2023-24538, DEBIAN-CVE-2023-24538, GHSA-v4m2-x4rp-hv22, GO-2023-1703, MINI-75v2-j9gh-p429, OESA-2024-2551, OESA-2024-2552, OESA-2024-2582, UBUNTU-CVE-2023-24538

## What is CVE-2023-24538?

CVE-2023-24538 is a critical cross-site scripting vulnerability in Golang Go, published on 6 Apr 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 (Improper Control of Generation of Code)

## Which versions are affected by CVE-2023-24538?

2 open source packages ship an affected version, including golang and stdlib. It affects 1 product.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `golang` | Bitnami | All versions | 1.19.8, 1.20.3 |
| `stdlib` | Go | All versions | 1.19.8, 1.20.3 |

Products: Golang Go.

## How do I fix CVE-2023-24538?

Upgrade golang to a fixed version for your release line: 1.19.8 or 1.20.3.

## Is CVE-2023-24538 being exploited?

There is no known exploitation of CVE-2023-24538 in the wild and no public exploit code.

Public exploit code:

- go CVE-2023-24538 patch issue resolver - Dunfell (github_poc): https://github.com/skulkarni-mv/goIssue_dunfell
- go CVE-2023-24538 patch issue resolver - Kirkstone (github_poc): https://github.com/skulkarni-mv/goIssue_kirkstone

## Other vulnerabilities in Golang Go

- [CVE-2020-0601](https://insights.sbomify.com/CVE-2020-0601/): Microsoft Windows CryptoAPI Spoofing (high 8.1, exploited in the wild)
- [CVE-2026-27143](https://insights.sbomify.com/CVE-2026-27143/): Missing bound checks can lead to memory corruption in safe Go in cmd/compile (critical 9.8)
- [CVE-2024-24790](https://insights.sbomify.com/CVE-2024-24790/): Unexpected behavior from Is methods for IPv4-mapped IPv6 addresses in net/netip (critical 9.8)
- [CVE-2023-39320](https://insights.sbomify.com/CVE-2023-39320/): Arbitrary code execution via go.mod toolchain directive in cmd/go (critical 9.8)
- [CVE-2023-24540](https://insights.sbomify.com/CVE-2023-24540/): Improper handling of JavaScript whitespace in html/template (critical 9.8)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2023-24538 and fix it if it is affected.

What it is: CVE-2023-24538 is a critical cross-site scripting vulnerability in Golang Go, published on 6 Apr 2023. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2023-24538 in the wild and no public exploit code.

Affected packages and fixed versions:
- golang (Bitnami): affected all versions; fixed in 1.19.8, 1.20.3
- stdlib (Go): affected all versions; fixed in 1.19.8, 1.20.3

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2023-24538/ (Markdown: https://insights.sbomify.com/CVE-2023-24538/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2023-24538
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2023-24538
- OSV: https://osv.dev/vulnerability/CVE-2023-24538

---
From sbomify Insights: https://insights.sbomify.com/CVE-2023-24538/
Summaries are generated and may contain mistakes; the official description above is the record.