Cross-Site Scripting (XSS) in homeassistant (CVE-2026-33045)
Summary
Cross-site scripting in homeassistant (CVE-2026-33045). Risk of unauthorized operations or information disclosure. Mitigation: upgrade to 2026.01 or later.
Original description
The description as published by the source.
Summary
The "remaining charge time"-sensor for mobile phones (imported/included from Android Auto it appears) is vulnerable to the same issue as CVE-2025-62172.
This also indicates that any sensor showing their name in the history-graph, is likely to be vulnerable to this issue.
Details
Another entity was found which displays the same behavior as in this issue: CVE-2025-62172
The History-graph card will sometimes display the name of the entity it is displaying, when the graph is shown as a line with values on the x and y axis. This appears to be vulnerable to Cross-Site scripting (XSS) as it does not have any output escaping or sanitization.
The PoC in this instance only shows HTML-injection in the form of the `` -tag being rendered as strike through, but the vulnerability also allows for injecting arbitrary tags which execute JavaScript, like the example given in the PoC description below.
PoC
- Register a new sensor (or device) or change the name of an existing one, which provides a location
- Change the name to something malicious, for example
test
For a new entity, it should work when setting the name. For old entities, go here:
PS: the example pictures show changing the name of the device-tracker entity, which is wrong. Just change the name of the remaining charge time-sensor in order to validate this finding
- Add a history graph card with the maliciou…
Source: OSV.dev (Open Source Vulnerabilities) NVD GitHub Advisory OSV
Auto-generated summary
Assembled by SecPulse from the source data (CVSS, CWE, affected versions) using templates — no AI involved. Check the original description and references below for exact details.
A vulnerability tracked as CVE-2026-33045 has been found in homeassistant.
Risk of unauthorized operations or information disclosure.
What to do: upgrade homeassistant to 2026.01 or later.
If unsure, ask your IT team or search "homeassistant CVE-2026-33045" on the vendor's site.
CVE-2026-33045 (homeassistant) — CWE-79
Patched: 2026.01 — apply immediately
Plan: 1) Audit SBOM/dependencies, 2) Stage→prod upgrade, 3) Add WAF/proxy monitoring on affected endpoints, 4) Hunt IOCs in logs.
Refs: see the GHSA / vendor advisory / patched release linked on this page.
Cross-site scripting (XSS) (CWE-79) exists in homeassistant.
Check the vendor advisory for the affected versions of homeassistant.
Severity: ?. Risk of unauthorized operations or information disclosure.
Update to 2026.01.
Until the patch is applied: disable the affected feature, apply WAF rules, or restrict access via network ACLs.
Search webserver/proxy logs for unusual request patterns matching this CVE's known IOCs. Run grep -r 'homeassistant' . against your dependency files (package-lock.json, requirements.txt, go.sum) to find affected services.
Response actions
Concrete steps and command examples for SOC/SRE teams to execute in order
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1Identify exposure identify
grep -r 'homeassistant' . | grep -v node_modulesリポジトリと本番環境の依存ファイル (package-lock.json / requirements.txt / go.sum / Gemfile.lock 等) で
homeassistantを grep し、稼働しているサービス・バージョンを把握する。 -
2Apply patch patch
Upgrade homeassistant to 2026.01ステージング環境で 2026.01 に上げて回帰テスト → 本番反映。回帰テストはアプリの主要ハッピーパスを含めること。
-
3Post-deployment verification verify
Confirm patched version is live in productionパッチ適用後、ステージングで PoC または同等の悪用パターンを再現して脆弱性が閉じたことを確認。本番ではアクセスログ・WAF でアラート再発が無いか継続監視。
Affected packages
References
- advisory nvd.nist.gov
- package github.com
- web github.com
- web github.com