High-severity (CVSS 10.0) remote-impact buffer overflow in widely used RTI Connext DDS middleware that can enable code execution and disruption in real-time/industrial systems.
CVE-2026-7866
Stack-based buffer overflow in RTI Connext Professional allowing code execution/crash.
Is CVE-2026-7866 being exploited?
Not confirmed. CVE-2026-7866 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 0.31% probability of exploitation in the next 30 days.
How severe is CVE-2026-7866?
CVE-2026-7866 is rated Critical with a CVSS score of 10.0. 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-2026-7866?
Yes. A fix has been recorded for CVE-2026-7866. The vendor advisory is the authority on the exact fixed version — apply it from there rather than from a summary.
What does CVE-2026-7866 affect?
CVE-2026-7866 affects RTI Connext Professional 7.4.0 before 7.7.0.1, RTI Connext Professional 7.0.0 before 7.3.1.6, RTI Connext Professional 6.1.0 before 6.1.*, RTI Connext Professional 6.0.0 before 6.0.*, and 3 further products or versions. Confirm the exact affected versions against the vendor advisory before deciding you are exposed.
What should I do about CVE-2026-7866?
Apply vendor fixes immediately; isolate and monitor Connext hosts.
Exploitation status reflects CISA's KEV catalog as we last synced it. Check the catalog directly.
Stack-based overflow can lead to remote code execution, arbitrary control or denial of service in systems using Connext core libraries.
Immediate action required
- affected>= 7.4.0 and < 7.7.0.1
- affected>= 7.0.0 and < 7.3.1.6
- affected>= 6.1.0 and < 6.1.*
- affected>= 6.0.0 and < 6.0.*
- affected>= 5.3.0 and < 5.3.*
- affected>= 5.2.0 and < 5.2.*
- affected>= 4.3x and < 5.1.*
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.