# CVE-2026-18459: RTI Connext Professional incorrect calculation in core libraries

Source: https://junglewise.ai/threats/cve-2026-18459-incorrect-calculation-vulnerability-in-rti-connext-professional  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-09-22. Updated: 2026-09-26  
License: CC BY 4.0 with a link back

CVE-2026-18459 · Severity: info · Published 2026-09-22

RTI Connext Professional is middleware that enables communication between distributed applications and systems. An incorrect calculation vulnerability in its core libraries could be exploited to abuse existing functionality, potentially compromising the reliability or integrity of systems that depend on the middleware for critical communications.

Technologies: [Rti Connext Professional](https://junglewise.ai/threats/technologies/connext-professional). Vendors: [Rti](https://junglewise.ai/threats/vendors/rti).

## Quick answers

**Is CVE-2026-18459 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-18459 being exploited in the wild.

**How severe is CVE-2026-18459?** Informational severity, published 22 September 2026.

**Which products and versions are affected?** Rti Connext Professional 7.4.0 before 7.7.0.1, 7.0.0 before 7.3.1.6, 6.1.0 before 6.1.x, 6.0.0 before 6.0.x, 5.3.0 before 5.3.x, 5.2.0 before 5.2.x, 4.1x before 5.1.x.

**Is there a fix for CVE-2026-18459?** No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.

**How is CVE-2026-18459 attacked?** It is in a software library.

**Am I affected by CVE-2026-18459?** Check whether you run Rti Connext Professional at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## Technical details

An incorrect calculation vulnerability exists in the Core Libraries component of RTI Connext Professional across multiple major versions. The vulnerability allows abuse of existing functionality through a calculation defect. The issue affects versions 7.4.0–7.7.0.0, 7.0.0–7.3.1.5, and earlier branches (6.x, 5.x, 4.x), with patches available in subsequent minor releases.

## Affected products

- RTI Connext Professional 7.4.0 before 7.7.0.1, 7.0.0 before 7.3.1.6, 6.1.0 before 6.1.x, 6.0.0 before 6.0.x, 5.3.0 before 5.3.x, 5.2.0 before 5.2.x, 4.1x before 5.1.x

## Timeline

- 2026-09-22: disclosed

## References

- [https://www.rti.com/vulnerabilities/](https://www.rti.com/vulnerabilities/)

## Related threats

- [RTI Connext Professional use-after-free in Security Plugins](https://junglewise.ai/threats/cve-2026-8849-use-after-free-vulnerability-in-rti-connext-professional-security)
- [RTI Connext Professional stack-based buffer overflow in core libraries](https://junglewise.ai/threats/cve-2026-7866-stack-based-buffer-overflow-vulnerability-in-rti-connext)
- [RTI Connext Professional out-of-bounds read in core libraries](https://junglewise.ai/threats/cve-2026-18626-out-of-bounds-read-vulnerability-in-rti-connext-professional-core)
- [RTI Connext Professional integer overflow in Core Libraries](https://junglewise.ai/threats/cve-2026-18462-integer-overflow-or-wraparound-improper-access-control)
- [RTI Connext Professional format string injection in Core Libraries](https://junglewise.ai/threats/cve-2026-18461-use-of-externally-controlled-format-string-vulnerability-in-rti)