Medium severity · published May 26, 2026
CVE-2026-8479
IEC 60870-5-104 used in bidirectional mode in RTU500 is vulnerable for a NULL pointer dereferencing, if a specially crafted sequence of messages is sent for a certain time,…
6.9
CVSS
0.2%
EPSS
No
On KEV
Description
IEC 60870-5-104 used in bidirectional mode in RTU500 is vulnerable
for a NULL pointer dereferencing, if a specially crafted
sequence of messages is sent for a certain time, causing
Denial of Service impact.
Product is only affected if IEC 60870-5-104 functionality in
bidirectional mode (BCI) is configured.
Exploitation
Is it being used?
Exploit prediction (EPSS)0.2% · higher than 6% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
RS
RTU500 series CMU firmware · Hitachi Energy
12.7.1 through 12.7.7; 13.5.1 through 13.5.4; 13.6.1 through 13.6.3; 13.7.1 through 13.7.8; 13.8.1 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-8479
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-8479
publisher.hitachienergy.com
https://publisher.hitachienergy.com/preview?DocumentID=8DBD000252&LanguageCode=en&DocumentPartId=&Action=Launch
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