CVE-2026-8066: CWE-23 Relative path traversal in Hitachi Energy RTU500 series CMU firmware
A directory traversal vulnerability in the file upload functionality of Hitachi Energy RTU500 end-of-life versions allows an unauthenticated attacker to write or overwrite arbitrary files on the device file system. Depending on the files affected, successful exploitation could result in unauthorized modification of device data or disruption of the device’s intended operation.
AI Analysis
Technical Summary
This vulnerability (CWE-23) in Hitachi Energy RTU500 series CMU firmware enables an unauthenticated attacker to perform directory traversal via the file upload feature. By exploiting this flaw, the attacker can write or overwrite arbitrary files on the device, potentially modifying critical device data or disrupting its intended functions. The flaw affects firmware versions >=9.0 and <12.0. No known exploits in the wild have been reported. The CVSS v3.1 base score is 9.1 (AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:H), reflecting network attack vector, low complexity, no privileges or user interaction required, and high impact on integrity and availability.
Potential Impact
Successful exploitation allows unauthenticated attackers to overwrite arbitrary files on the device, which can lead to unauthorized modification of device data or disruption of device operation. This can compromise the integrity and availability of the affected device.
Mitigation Recommendations
No patch or official fix information is provided in the available data. Patch status is not yet confirmed — check the vendor advisory for current remediation guidance.
CVE-2026-8066: CWE-23 Relative path traversal in Hitachi Energy RTU500 series CMU firmware
Description
A directory traversal vulnerability in the file upload functionality of Hitachi Energy RTU500 end-of-life versions allows an unauthenticated attacker to write or overwrite arbitrary files on the device file system. Depending on the files affected, successful exploitation could result in unauthorized modification of device data or disruption of the device’s intended operation.
CVSS v3.1
Score 9.1critical
Affected software
Hitachi Energy
RTU500 series CMU firmware
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
This vulnerability (CWE-23) in Hitachi Energy RTU500 series CMU firmware enables an unauthenticated attacker to perform directory traversal via the file upload feature. By exploiting this flaw, the attacker can write or overwrite arbitrary files on the device, potentially modifying critical device data or disrupting its intended functions. The flaw affects firmware versions >=9.0 and <12.0. No known exploits in the wild have been reported. The CVSS v3.1 base score is 9.1 (AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:H), reflecting network attack vector, low complexity, no privileges or user interaction required, and high impact on integrity and availability.
Potential Impact
Successful exploitation allows unauthenticated attackers to overwrite arbitrary files on the device, which can lead to unauthorized modification of device data or disruption of device operation. This can compromise the integrity and availability of the affected device.
Mitigation Recommendations
No patch or official fix information is provided in the available data. Patch status is not yet confirmed — check the vendor advisory for current remediation guidance.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- Hitachi Energy
- Date Reserved
- 2026-05-07T05:51:57.867Z
- Cvss Version
- 3.1
- State
- PUBLISHED
Threat ID: 6abb85e3f7a7c5410623217e
Added to database: 09/29/2026, 09:33:23 UTC
Last enriched: 09/29/2026, 09:47:45 UTC
Last updated: 09/29/2026, 18:20:12 UTC
Views: 12
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