Vulnerability-Lookup

GHSA-R3V5-J696-5GRQ

Vulnerability from github – Published: 2026-07-21 18:31 – Updated: 2026-07-21 18:31

Details

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

4.7 (Medium)


                  
                    CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:C/C:L/I:L/A:N

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

Show details on source website

JSON

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{
  "affected": [],
  "aliases": [
    "CVE-2026-64823"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-79"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-07-21T16:17:21Z",
    "severity": "LOW"
  },
  "details": "Home Assistant Core before 2026.5.4 contains a cross-site scripting vulnerability in the Shelly integration\u0027s async_get_media_image() method that allows attackers controlling a Shelly device\u0027s 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.",
  "id": "GHSA-r3v5-j696-5grq",
  "modified": "2026-07-21T18:31:02Z",
  "published": "2026-07-21T18:31:01Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-64823"
    },
    {
      "type": "WEB",
      "url": "https://github.com/home-assistant/core/pull/171585"
    },
    {
      "type": "WEB",
      "url": "https://github.com/home-assistant/core/commit/894a68acb678afc382fe5ea9002e61ab7f862011"
    },
    {
      "type": "WEB",
      "url": "https://github.com/home-assistant/core/releases/tag/2026.5.4"
    },
    {
      "type": "WEB",
      "url": "https://www.vulncheck.com/advisories/home-assistant-core-xss-via-shelly-media-player-py-thumb-uri"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:C/C:L/I:L/A:N",
      "type": "CVSS_V3"
    },
    {
      "score": "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/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X",
      "type": "CVSS_V4"
    }
  ]
}

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

Title

Home Assistant Core < 2026.5.4 XSS via Shelly media_player.py thumb URI

Summary

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 (v2.0.3)

CWE

CWE-79 - Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

Assigner

VulnCheck

References

4 references

URL	Tags
https://github.com/home-assistant/core/releases/t…	release-notes
https://github.com/home-assistant/core/pull/171585	issue-tracking
https://github.com/home-assistant/core/commit/894…	patch
https://www.vulncheck.com/advisories/home-assista…	third-party-advisory

Impacted products

1 product

Vendor	Product	Version
home-assistant	Home Assistant Core	Affected: 0 , < 2026.5.4 (semver)

Date Public

2026-05-20 00:00

Credits

Harish Kolla (@Har1sh-k)

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2026-64823",
                "options": [
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                    "Exploitation": "none"
                  },
                  {
                    "Automatable": "no"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-07-22T14:12:03.484754Z",
                "version": "2.0.3"
              },
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        "providerMetadata": {
          "dateUpdated": "2026-07-22T14:12:16.922Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
          "defaultStatus": "affected",
          "packageURL": "pkg:github/home-assistant/core",
          "product": "Home Assistant Core",
          "repo": "https://github.com/home-assistant/core",
          "vendor": "home-assistant",
          "versions": [
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              "lessThan": "2026.5.4",
              "status": "affected",
              "version": "0",
              "versionType": "semver"
            }
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      ],
      "cpeApplicability": [
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          "nodes": [
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              "cpeMatch": [
                {
                  "criteria": "cpe:2.3:a:home-assistant:home-assistant:*:*:*:*:*:*:*:*",
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                }
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      ],
      "metrics": [
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            "Recovery": "NOT_DEFINED",
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    "datePublished": "2026-07-21T15:16:03.790Z",
    "dateReserved": "2026-07-20T18:27:48.160Z",
    "dateUpdated": "2026-07-22T14:12:16.922Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}

Sightings

Author	Source	Type	Date	Other

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

Detection rules are retrieved from Rulezet.

The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.

Action not permitted

GHSA-R3V5-J696-5GRQ

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

Tags

Sightings

Nomenclature