- Critical 9.1
CVE-2026-8065
An authentication bypass vulnerability in the firmware update endpoint of Hitachi Energy RTU500 end-of-life versions allows an unauthenticated attacker to upload arbitrary firmware through a crafted POST request. Successful exploitation could allow the attacker to modify device functionality or compromise the integrity or availability of the device.
Scores
The facts
- Published
- 29 September 2026
- Last changed
- 29 September 2026
- NVD status
- Awaiting Analysis
- Severity
- Critical, CVSS 9.1 out of 10 (version 3.1)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:H - Weakness
- Known exploited
- Not in the CISA Known Exploited Vulnerabilities catalogue in this build.
- EPSS
- 0.6% chance of exploitation activity in the next 30 days (percentile 46).
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