# CVE-2026-72850: Budibase before 3.40.0 Arbitrary File Write via Path Traversal

> Authenticated builders can exploit path traversal in S3 key sanitization to write arbitrary files during workspace export, potentially leading to code execution.

- **Severity:** Critical 9.4 (`CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H`)
- **Exploited in the wild:** Not known
- **Login needed:** An administrator
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 13 Aug 2026
- **Updated:** 8 Oct 2026
- **Also known as:** GHSA-ccjw-whgg-h4gh, GHSA-pxwc-66g3-5f27

## What is CVE-2026-72850?

CVE-2026-72850 is a critical path traversal vulnerability in budibase server, published on 13 Aug 2026. An attacker needs administrator access to exploit it, with no action from the victim.

### Official description

Budibase before 3.40.0 fails to properly sanitize S3 object keys, allowing authenticated builders to upload files with traversal sequences that are preserved during export. Attackers can craft filenames containing .. segments that escape the temporary directory during workspace export, writing arbitrary content to any path writable by the Budibase process.

Weakness: CWE-22 (Improper Limitation of a Pathname to a Restricted Directory)

## Which versions are affected by CVE-2026-72850?


## How do I fix CVE-2026-72850?

No fix has been published for CVE-2026-72850 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-72850 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-72850 exists.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-72850 and fix it if it is affected.

What it is: CVE-2026-72850 is a critical path traversal vulnerability in budibase server, published on 13 Aug 2026. An attacker needs administrator access to exploit it, with no action from the victim.
Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-72850 exists.

Affected product: budibase server. 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-2026-72850/ (Markdown: https://insights.sbomify.com/CVE-2026-72850/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-72850
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-72850
- OSV: https://osv.dev/vulnerability/CVE-2026-72850

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-72850/
Summaries are generated and may contain mistakes; the official description above is the record.