---
title: "CVE-2024-3955: CraftBeerPi 4 allows arbitrary code execution"
url: https://erroneo.us/security/cve/CVE-2024-3955/
description: "CVE-2024-3955 (cbpi4 (PyPI)): URL GET parameter \"logtime\" utilized within the \"downloadlog\" function from \"cbpi/httpendpoints/httpsystem.py\" is subsequently…"
type: vulnerability-record
section: "Security Digest"
date_published: 2024-05-02
date_modified: 2024-08-01
publisher: erroneo.us
author: erroneo.us Security Desk
cve: "CVE-2024-3955"
kev: false
cvss: 9.8
epss: 0.01149
license: All rights reserved. Quote with attribution and a link.
---

# CVE-2024-3955: CraftBeerPi 4 allows arbitrary code execution

**Signal:** Critical and remotely reachable. No known exploitation yet, but it is network-reachable without credentials. (Computed from CISA KEV, EPSS and CVSS; not an editorial verdict.)

## Should you act?

- No confirmed exploitation. It is not in CISA’s KEV catalog and CISA’s SSVC assessment records no known exploitation. That can change quickly after a public write-up; re-check if you are affected.
- EPSS 1.1% , percentile 67: FIRST’s model estimates a 1.1% chance of exploitation activity in the next 30 days, higher than 67% of all scored CVEs (moderate). EPSS is a probability, not a verdict.
- Remotely reachable with no login and no user interaction. If the vulnerable service is exposed to the internet, prioritize it.
- Only applies if your dependency tree includes cbpi4 (PyPI) >= 4.0.0.58, < 4.4.1.a1, fixed in 4.4.1.a1 . Check your lockfile, including transitive dependencies.

## What it is

URL GET parameter "logtime" utilized within the "downloadlog" function from "cbpi/httpendpoints/httpsystem.py" is subsequently passed to the "os.system" function in "cbpi/controller/systemcontroller.py" without prior validation allowing to execute arbitrary code.This issue affects CraftBeerPi 4: from 4.0.0.58 (commit 563fae9) before 4.4.1.a1 (commit 57572c7).

## Affected packages

- PyPI `cbpi4` >= 4.0.0.58, < 4.4.1.a1 → fixed: 4.4.1.a1

## Affected products (CVE record)

- PiBrewing CraftBeerPi 4: 4.0.0.58 (commit 563fae9) < 4.4.1.a1 (commit 57572c7)
- CraftBeerPi - Brewing Controller CraftBeerPi 4: 4.0.0.58 (commit 563fae9) <= *

## Severity

- CISA-ADP CVSS 3.1: 9.8 `CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H`
- GitHub CVSS 3.1: 9.8 `CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H`

## Exploitation

- CISA KEV: not listed (no confirmed in-the-wild exploitation known to CISA).
- CISA SSVC assessment: exploitation none , automatable yes , technical impact total .
- FIRST EPSS (model of 2026-10-21): 1.15% probability of exploitation activity in the next 30 days; percentile 67.

## Sources

- [GitHub Advisory GHSA-4f92-w438-f484](https://github.com/advisories/GHSA-4f92-w438-f484)
- [CVE.org record CVE-2024-3955](https://www.cve.org/CVERecord?id=CVE-2024-3955)
- [NVD entry CVE-2024-3955](https://nvd.nist.gov/vuln/detail/CVE-2024-3955)
- [cert.pl](https://cert.pl/en/posts/2024/05/CVE-2024-3955/)
- [cert.pl](https://cert.pl/posts/2024/05/CVE-2024-3955/)
- [github.com](https://github.com/PiBrewing/craftbeerpi4/issues/132)

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Source page: https://erroneo.us/security/cve/CVE-2024-3955/ · Security Digest: https://erroneo.us/security/ · More: https://erroneo.us/llms.txt