What is CVE-2024-27287?

CVE-2024-27287 is a medium-severity vulnerability in Esphome, classified under Cross-site Scripting. CVSS score: 6.5/10. Published 2024-03-06.

How severe is CVE-2024-27287?

Medium severity. CVSS v3 base score is 6.5 out of 10.

XSS in Esphome

CVE-2024-27287

ESPHome is a system to control your ESP8266/ESP32 for Home Automation systems. Starting in version 2023.12.9 and prior to version 2024.2.2, editing the configuration file API in dashboard component of ESPHome version 2023.12.9 (command line installation and Home Assistant add-on) serves unsanitized data with `Content-Type: text/html; charset=UTF-8`, allowing a remote authenticated user to inject arbitrary web script and exfiltrate session cookies via Cross-Site scripting. It is possible for a malicious authenticated user to inject arbitrary Javascript in configuration files using a POST request to the /edit endpoint, the configuration parameter allows to specify the file to write. To trigger the XSS vulnerability, the victim must visit the page` /edit?configuration=[xss file]`. Abusing this vulnerability a malicious actor could perform operations on the dashboard on the behalf of a logged user, access sensitive information, create, edit and delete configuration files and flash firmware on managed boards. In addition to this, cookies are not correctly secured, allowing the exfiltration of session cookie values. Version 2024.2.2 contains a patch for this issue.

Vulnerability class: XSS (Cross-Site Scripting)

Published 2024-03-06 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 6.5 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:N.

EPSS exploit prediction

EPSS: 0.007 (50.7th percentile), scored 2026-10-03.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 51st percentile — 50.7% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.007 · newest: 0.007 · change: 0.000

Affected products

Esphome — versions >= 2023.12.9, < 2024.2.2

Weakness classification (CWE)

CWE-79 — Cross-site Scripting

References

github.com/esphome/esphome/security/advisories/GHSA-9p43-hj5j-96h5 (Vendor Advisory, Technical Description)
github.com/esphome/esphome/commit/37d2b3c7977a4ccbec59726ca7549cb776661455 (Patch)

Frequently asked questions

What is CVE-2024-27287?: CVE-2024-27287 is a medium-severity vulnerability in Esphome, classified under Cross-site Scripting. CVSS score: 6.5/10. Published 2024-03-06.
How severe is CVE-2024-27287?: Medium severity. CVSS v3 base score is 6.5 out of 10.