core: Improper Neutralization of Script-Related HTML Tags in a Web Page
CVE-2026-91130 is a critical-severity improper neutralization of script-related HTML tags in a web page vulnerability in core from Home-assistant, with a CVSS 4.0 base score of 9.3 out of 10. It can be exploited remotely over the network by an attacker with a low-privileged account, but only if a user takes part, for example by opening a link or file. Affected core versions: < 2026.7.0. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 0.48% chance of exploitation within 30 days, which is low compared with other CVEs.
Critical severity: a successful attack would have severe impact.
What to do
- Check which version of core you run against the affected versions below, and install the vendor's latest release.
- Read the advisory on github.com for workarounds and exact fixed builds.
- Because the attack needs a user to take part, warn users about unexpected links and files related to this product until it is patched.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| Home-assistant | core | < 2026.7.0 | Not stated |
Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.
How the severity score breaks down
- Attack vector
- NetworkCan be exploited remotely over a network, including the internet.
- Attack complexity
- LowNo special conditions are needed; the attack works reliably.
- Attack requirements
- NoneThe attack does not depend on a particular deployment or configuration.
- Privileges required
- LowA basic user account is enough.
- User interaction
- ActiveA user must deliberately do something unusual, such as dismissing a warning.
- Confidentiality (vulnerable system)
- HighSerious loss of confidentiality on the vulnerable system.
- Integrity (vulnerable system)
- HighSerious loss of integrity on the vulnerable system.
- Availability (vulnerable system)
- HighSerious loss of availability on the vulnerable system.
- Confidentiality (other systems)
- HighSerious loss of confidentiality on systems beyond the vulnerable one.
- Integrity (other systems)
- HighSerious loss of integrity on systems beyond the vulnerable one.
- Availability (other systems)
- HighSerious loss of availability on systems beyond the vulnerable one.
Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:A/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H/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. Scored by CNA (github.com).
Official description
Home Assistant is open source home automation software focused on local control and privacy. Prior to 2026.7.0, the Statistics Graph card in src/components/chart/statistics-chart.ts passed entity names through getStatisticLabel and computeStateName and interpolated param.seriesName into ECharts tooltip HTML without escaping. An authenticated user or an integration that supplies a malicious default entity name could cause script-related HTML to execute when a viewer hovered over a data point. Mean, State, Sum, and Change fields in the default Line chart configuration were affected, while Bar charts were not. This issue is fixed in version 2026.7.0.
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Improper Neutralization of Script-Related HTML Tags in a Web Page
The product receives input from an upstream component, but it does not neutralize or incorrectly neutralizes special characters such as <, >, and & that could be interpreted as web-scripting elements when they are sent to a downstream component that processes web pages.
How developers prevent this class of flaw
- With Struts, write all data from form beans with the bean's filter attribute set to true.
More Improper Neutralization of Script-Related HTML Tags in a Web Page vulnerabilities (CWE-80)
Timeline
- CVE record published.
- CISA published its SSVC assessment (exploitation: poc, automatable: no, technical impact: total).
- Record last changed materially (score, affected products, status or references).
References
Patches and release notes
Other vulnerabilities in core
- 7.1 High severity
- 7.1 High severity
- 7.5 High severity
- 7.1 High severity
- 7.6 High severity
- 8.3 High severity
Recent Improper Neutralization of Script-Related HTML Tags in a Web Page vulnerabilities
- 7.0 High severity
- 7.5 High severity
- 8.5 High severity
- 8.9 High severity
- 8.9 High severity
- 8.6 High severity
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