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CVE-2026-18459NVD status: Awaiting Analysis

Connext Professional: Incorrect Calculation

Published Updated By the CyberSecBulletin desk

CVE-2026-18459 is a high-severity incorrect calculation vulnerability in Connext Professional from RTI, with a CVSS 4.0 base score of 8.7 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. The record lists versions 7.7.0.1, 7.3.1.6, 6.1.* as the first without the flaw, so updating Connext Professional to one of those releases or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 0.43% chance of exploitation within 30 days, which is low compared with other CVEs.

Next patch cycle

High severity with no evidence of exploitation so far.

What to do

  1. Update Connext Professional to 7.7.0.1 or 7.3.1.6 or 6.1.* or 6.0.*, whichever matches your release line, or a later version.
  2. Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.

Affected products and versions

VendorProductAffected versionsFixed in
RTIConnext Professional7.4.0 up to, but not including, 7.7.0.1; 7.0.0 up to, but not including, 7.3.1.6; 6.1.0 up to, but not including, 6.1.*; 6.0.0 up to, but not including, 6.0.*; 5.3.0 up to, but not including, 5.3.*; 5.2.0 up to, but not including, 5.2.*; 4.1x up to, but not including, 5.1.*7.7.0.1, 7.3.1.6, 6.1.*, 6.0.*, 5.3.*, 5.2.*

Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.

How the severity score breaks down

Attack vector
NetworkCan be exploited remotely over a network, including the internet.
Attack complexity
LowNo special conditions are needed; the attack works reliably.
Attack requirements
NoneThe attack does not depend on a particular deployment or configuration.
Privileges required
NoneNo account or login is needed.
User interaction
NoneNo action by a victim is required.
Confidentiality (vulnerable system)
NoneNo loss of confidentiality on the vulnerable system.
Integrity (vulnerable system)
NoneNo loss of integrity on the vulnerable system.
Availability (vulnerable system)
HighSerious loss of availability on the vulnerable system.
Confidentiality (other systems)
NoneNo loss of confidentiality on systems beyond the vulnerable one.
Integrity (other systems)
NoneNo loss of integrity on systems beyond the vulnerable one.
Availability (other systems)
NoneNo loss of availability on systems beyond the vulnerable one.

Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X. Scored by CNA.

Official description

Incorrect Calculation vulnerability in RTI Connext Professional (Core Libraries) allows Abuse Existing Functionality. This issue affects Connext Professional: from 7.4.0 before 7.7.0.1, from 7.0.0 before 7.3.1.6, from 6.1.0 before 6.1.*, from 6.0.0 before 6.0.*, from 5.3.0 before 5.3.*, from 5.2.0 before 5.2.*, from 4.1x before 5.1.*.

Source: the CVE record as published by its numbering authority, via NVD and CVE.org.

The underlying weakness: Incorrect Calculation

The product performs a calculation that generates incorrect or unintended results that are later used in security-critical decisions or resource management.

How developers prevent this class of flaw

  • Understand your programming language's underlying representation and how it interacts with numeric calculation. Pay close attention to byte size discrepancies, precision, signed/unsigned distinctions, truncation, conversion and casting between types, not-a-number calculations, and how your language handles numbers that are too large or too small for its underlying representation.
  • Perform input validation on any numeric input by ensuring that it is within the expected range. Enforce that the input meets both the minimum and maximum requirements for the expected range.
  • Use the appropriate type for the desired action. For example, in C/C++, only use unsigned types for values that could never be negative, such as height, width, or other numbers related to quantity.

More Incorrect Calculation vulnerabilities (CWE-682)

Timeline

  1. CVE record published.
  2. CISA published its SSVC assessment (exploitation: none, automatable: yes, technical impact: partial).

References

Other vulnerabilities in Connext Professional

All Connext Professional vulnerabilities

Recent Incorrect Calculation vulnerabilities

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