Cyber Resilience

CVE-2026-91130

XSS

XSS
Published
22 September 2026
Modified
23 September 2026
CVSS Score v4 9.3
Click a component to see what it means
Raw vectorCVSS: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
EPSS Score 0.0039 30th percentile
Risk Priority 70 floored blend · peak EPSS

CVSS and EPSS are reproduced from their sources (NVD, FIRST EPSS). Risk Priority is our own derived reading, not an NVD score.

Summary

CVE-2026-91130 is a critical-severity Basic XSS (CWE-80) vulnerability. Its CVSS base score is 9.3 (Critical).

Operationally, exploitation aligns with the MITRE ATT&CK technique Drive-by Compromise (T1189); ranked at the 30th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.

The strongest mitigations our analysis identified map to SA-11 (Developer Testing and Evaluation) and SA-3 (System Development Life Cycle) — see the control section below for these in your framework.

OWASP Top 10 for Web (2025)

A05:2025 Injection

EU & UK References

Vulnerability Data

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…

more

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.

CWE(s)
CWE-80

Related Threats

MITRE ATT&CK Enterprise Techniques

T1189 Drive-by Compromise Initial Access
Adversaries may gain access to a system through a user visiting a website over the normal course of browsing.
attack.mitre.org →
T1539 Steal Web Session Cookie Credential Access
An adversary may steal web application or service session cookies and use them to gain access to web applications or Internet services as an authenticated user without needing credentials.
attack.mitre.org →
T1659 Content Injection Initial Access
Adversaries may gain access and continuously communicate with victims by injecting malicious content into systems through online network traffic.
attack.mitre.org →
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2025-12803Shared CWE-80
CVE-2026-44264Shared CWE-80
CVE-2025-65924Shared CWE-80
CVE-2023-48285Shared CWE-80
CVE-2025-10496Shared CWE-80
CVE-2026-39642Shared CWE-80
CVE-2025-71331Shared CWE-80
CVE-2025-57730Shared CWE-80
CVE-2024-4214Shared CWE-80
CVE-2024-50344Shared CWE-80

Affected Assets

Mitigating Controls

Control response

Prevent
Stop it (NIST 800-53)

—

Detect
Catch it (NIST detect / respond)

—

Harden
Shrink the surface (DISA STIG)

—

Validate
Prove the fix (OWASP ASVS)
  • V1.2.1
  • V1.3.1
  • V1.3.3
  • V1.3.4

Mitigating Controls (NIST 800-53 r5) AI

SA-11 Developer Testing and Evaluation partial match

Developer testing and evaluation can discover missing or incorrect neutralization of script tags through targeted XSS test cases.

SA-3 System Development Life Cycle partial match

XSS is consistent with a weak SDLC but is not diagnostic of it: many specific controls sit between the SDLC and this defect class.

SA-8 Security and Privacy Engineering Principles partial match

Secure engineering principles include mandatory output encoding and neutralization of HTML metacharacters to stop injection at the source.

SI-10 Information Input Validation partial match

Input validation explicitly requires checking and neutralizing untrusted web inputs containing script-related characters before they reach a downstream renderer.

Mitigating Controls (NIST CSF 2.0) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.

PR.PS-06 partial match
prevents

Secure SDLC practices directly require output encoding and input validation that prevent basic XSS.

Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.

A.8.25 Secure development life cycle partial match
prevents

Secure SDLC mandates input validation and output encoding that directly prevent basic XSS.

A.8.26 Application security requirements partial match
prevents

Application security requirements explicitly call for neutralization of script-related HTML tags.

A.8.28 Secure coding partial match
prevents

Secure coding standards require proper escaping of <, >, & to block XSS.

A.8.29 Security testing in development and acceptance partial match
finds

Security testing in development catches unneutralized script tags before release.

References