CVE-2026-64823 (GCVE-0-2026-64823)

Vulnerability from cvelistv5 – Published: 2026-07-21 15:16 – Updated: 2026-07-22 14:12 X_Open Source
VLAI
Title
Home Assistant Core < 2026.5.4 XSS via Shelly media_player.py thumb URI
Summary
Home Assistant Core before 2026.5.4 contains a cross-site scripting vulnerability in the Shelly integration's async_get_media_image() method that allows attackers controlling a Shelly device's thumb field to serve arbitrary HTML content by supplying a data URI with a text/html content type without validation against an image-only allowlist. Attackers can cause the media player proxy endpoint to serve attacker-controlled bytes with Content-Type text/html in the Home Assistant web origin, enabling theft of session tokens from local storage and authenticated calls to sensitive service endpoints including lock, alarm, and cover controls.
Severity
2.1 (Low)
CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:A/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N
4.7 (Medium)
CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:C/C:L/I:L/A:N
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-07-22 14:12 UTC
CWE
  • CWE-79 - Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
Assigner
VulnCheck CNA under the mitre root
CNA scorecard B 84/100 over 7131 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
home-assistant Home Assistant Core Affected: 0 , < 2026.5.4 (semver)
    cpe:2.3:a:home-assistant:home-assistant:*:*:*:*:*:*:*:*
Create a notification for this product.
Date Public
2026-05-20 00:00
Credits
Harish Kolla (@Har1sh-k)
Show details on NVD website
To clipboard 

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