# CVE-2020-28367: Arbitrary code execution via the go command with cgo in cmd/go

> Attackers can execute arbitrary code during build time by injecting malicious gcc flags via cgo directives in Go projects.

- **Severity:** High 7.5 (`CVSS:3.1/AV:N/AC:H/PR:N/UI:R/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:** A user has to click or open something
- **Fix available:** Yes
- **Published:** 18 Nov 2020
- **Updated:** 4 Aug 2024
- **Also known as:** BIT-golang-2020-28367, DEBIAN-CVE-2020-28367, GHSA-827f-m9xx-4cfw, GO-2022-0476, UBUNTU-CVE-2020-28367

## What is CVE-2020-28367?

CVE-2020-28367 is a high-severity code injection vulnerability in Golang Go, published on 18 Nov 2020. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.

### Official description

Code injection in the go command with cgo before Go 1.14.12 and Go 1.15.5 allows arbitrary code execution at build time via malicious gcc flags specified via a #cgo directive.

Weakness: CWE-94 (Improper Control of Generation of Code)

## Which versions are affected by CVE-2020-28367?

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


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `golang` | Bitnami | All versions | 1.14.12, 1.15.5 |
| `toolchain` | Go | All versions | 1.14.12, 1.15.5 |

Products: Golang Go.

## How do I fix CVE-2020-28367?

Upgrade golang to a fixed version for your release line: 1.14.12 or 1.15.5.

## Is CVE-2020-28367 being exploited?

There is no known exploitation of CVE-2020-28367 in the wild and no public exploit code.

## 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-2020-28367 and fix it if it is affected.

What it is: CVE-2020-28367 is a high-severity code injection vulnerability in Golang Go, published on 18 Nov 2020. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.
Exploitation: There is no known exploitation of CVE-2020-28367 in the wild and no public exploit code.

Affected packages and fixed versions:
- golang (Bitnami): affected all versions; fixed in 1.14.12, 1.15.5
- toolchain (Go): affected all versions; fixed in 1.14.12, 1.15.5

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-2020-28367/ (Markdown: https://insights.sbomify.com/CVE-2020-28367/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2020-28367
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2020-28367
- OSV: https://osv.dev/vulnerability/CVE-2020-28367

---
From sbomify Insights: https://insights.sbomify.com/CVE-2020-28367/
Summaries are generated and may contain mistakes; the official description above is the record.