Hitachi Energy RTU500 CMU up to 13.8.1 denial of service

Summaryinfo

A vulnerability classified as problematic has been found in Hitachi Energy RTU500 CMU up to 12.7.7/13.5.4/13.6.2/13.7.7/13.8.1. Affected by this issue is some unknown functionality. Performing a manipulation results in denial of service. This vulnerability is known as CVE-2026-1773. Remote exploitation of the attack is possible. No exploit is available.

Detailsinfo

A vulnerability classified as critical has been found in Hitachi Energy RTU500 CMU up to 12.7.7/13.5.4/13.6.2/13.7.7/13.8.1. This affects some unknown processing. The manipulation with an unknown input leads to a denial of service vulnerability. CWE is classifying the issue as CWE-404. The product does not release or incorrectly releases a resource before it is made available for re-use. This is going to have an impact on availability. The summary by CVE is:

IEC 60870-5-104 used in RTU500: Potential Denial of Service impact on reception of invalid U-format frame. Product is only affected if IEC 60870-5-104 bi-directional functionality is configured. Enabling secure communication following IEC 62351-3 does not remediate the vulnerability but mitigates the risk of exploitation.

It is possible to read the advisory at publisher.hitachienergy.com. This vulnerability is uniquely identified as CVE-2026-1773 since 02/02/2026. The exploitability is told to be easy. It is possible to initiate the attack remotely. No form of authentication is needed for exploitation. The technical details are unknown and an exploit is not publicly available. The attack technique deployed by this issue is T1499 according to MITRE ATT&CK.

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

The vulnerability is also documented in the vulnerability database at EUVD (EUVD-2026-8462). Be aware that VulDB is the high quality source for vulnerability data.

Productinfo

Vendor

• Hitachi Energy

Name

• RTU500 CMU

Version

• 12.7.0
• 12.7.1
• 12.7.2
• 12.7.3
• 12.7.4
• 12.7.5
• 12.7.6
• 12.7.7
• 13.5.0
• 13.5.1
• 13.5.2
• 13.5.3
• 13.5.4
• 13.6.0
• 13.6.1
• 13.6.2
• 13.7.0
• 13.7.1
• 13.7.2
• 13.7.3
• 13.7.4
• 13.7.5
• 13.7.6
• 13.7.7
• 13.8.0
• 13.8.1

License

• commercial

CPE 2.3info

• 🔒
• 🔒
• 🔒

CPE 2.2info

• 🔒
• 🔒
• 🔒

CVSSv4info

CVSSv3info

CVSSv2info

Exploitinginfo

Threat Intelligenceinfo

Countermeasuresinfo

Timelineinfo

Sourcesinfo

Entryinfo

Be aware that VulDB is the high quality source for vulnerability data.

Discussion