Answer in brief
CVE-2026-17539 records a Medium severity (CVSS 5.9) vulnerability in CISA ADP Vulnrichment. The current sources do not mark it as known exploited. The current feed maps Hitachi Energy/RTU500 series CMU firmware (generic), Hitachi Energy/RTU500 series CMU firmware (generic). Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
CVSS is 5.9. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.
Analysis status
Analysis pending evidence review
Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.
The current feed maps Hitachi Energy/RTU500 series CMU firmware (generic), Hitachi Energy/RTU500 series CMU firmware (generic). Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| Hitachi Energy/RTU500 series CMU firmwaregeneric | 12.7.1 || 13.5.1 || 13.6.1 || 13.7.1 || 13.8.1 | Not reported |
| Hitachi Energy/RTU500 series CMU firmwaregeneric | >=12.7.1 <=12.7.7 || >=13.5.1 <=13.5.4 || >=13.6.1 <=13.6.3 || >=13.7.1 <=13.7.8 || >=13.8.1 <=13.8.2 | Not reported |
Published upstream
Sep 3, 2026
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Sep 3, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Sep 3, 2026
RTU500 has a vulnerability, where high-load scenarios, such as sending GI requests at short intervals, may cause a NULL pointer dereference in the last entry of the enhanced message queue. This can cause a BCI_IEC104 fatal write error, resulting in connection interruption and restart, and ultimately a denial of service for bidirectional IEC 60870-5-104 communication.
Quoted source text, attributed separately from HOL analysis.