# CVE-2021-47900: Gila CMS < 2.0.0 - Remote Code Execution

> Unauthenticated attackers can execute arbitrary system commands via PHP code injection in the User-Agent header of Gila CMS.

- **Severity:** Critical 9.3 (`CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 27 Jan 2026
- **Updated:** 5 Mar 2026
- **Also known as:** GHSA-xq2p-83g5-rqxp

## What is CVE-2021-47900?

CVE-2021-47900 is a critical code injection vulnerability in Gila CMS, published on 27 Jan 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

Gila CMS versions prior to 2.0.0 contain a remote code execution vulnerability that allows unauthenticated attackers to execute arbitrary system commands through manipulated HTTP headers. Attackers can inject PHP code in the User-Agent header with shell_exec() to run system commands by sending crafted requests to the admin endpoint.

Weakness: CWE-98 (Improper Control of Filename for Include/Require Statement in PHP Program)

## Which versions are affected by CVE-2021-47900?


## How do I fix CVE-2021-47900?

No fix has been published for CVE-2021-47900 yet. Limit exposure of the affected software until one is available.

## Is CVE-2021-47900 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2021-47900 exists.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2021-47900 and fix it if it is affected.

What it is: CVE-2021-47900 is a critical code injection vulnerability in Gila CMS, published on 27 Jan 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2021-47900 exists.

Affected product: Gila CMS. No package-level version data is available, so check the vendor advisory linked from the reference page.

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-2021-47900/ (Markdown: https://insights.sbomify.com/CVE-2021-47900/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2021-47900
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2021-47900
- OSV: https://osv.dev/vulnerability/CVE-2021-47900

---
From sbomify Insights: https://insights.sbomify.com/CVE-2021-47900/
Summaries are generated and may contain mistakes; the official description above is the record.