CVE-2026-66360
ISO Presentation/MMS parsing flaw allows remote DoS via crafted TCP/102 packet
Is CVE-2026-66360 being exploited?
Not confirmed. CVE-2026-66360 does not appear in CISA's Known Exploited Vulnerabilities catalog, which records only exploitation that has been observed and reported publicly. That is evidence of absence of a report, not evidence the flaw is unattacked. EPSS currently estimates a 0.28% probability of exploitation in the next 30 days.
How severe is CVE-2026-66360?
CVE-2026-66360 is rated High with a CVSS score of 8.7. Severity describes how bad exploitation would be, not how likely it is: pair it with exploitation evidence before deciding what to patch first.
Is there a patch for CVE-2026-66360?
Not known from our data. No patch reference has been recorded for CVE-2026-66360, which is not the same as no patch existing — a fix may have shipped without a tagged reference, or after this record was written. The vendor advisory is the only authority on whether a fix exists, and mitigations may be available regardless.
What does CVE-2026-66360 affect?
CVE-2026-66360 affects ISO Presentation layer implementations, MMS servers/clients, IEC 61850 devices, Systems listening on TCP/102. Confirm the exact affected versions against the vendor advisory before deciding you are exposed.
What should I do about CVE-2026-66360?
Block/inspect TCP/102 from untrusted networks; apply vendor patches when released.
Exploitation status reflects CISA's KEV catalog as we last synced it. Check the catalog directly.
Remote denial of service: crafted TCP/102 (MMS) connection with zero-length field triggers bounded heap over-read and process crash.
Immediate action required
- affected< 1.6.2
As published in the CVE Program record. A version outside these ranges is not a statement that it is unaffected — vendors sometimes understate a range, and distribution-backported builds carry upstream numbers that do not reflect what was patched into them.