# CVE-2026-18458: Memory corruption in Connext Professional

> An out-of-bounds read and type confusion vulnerability in RTI Connext Professional allows attackers to overread buffers, potentially leading to information disclosure or crashes.

- **Severity:** Medium 6.8 (`CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 22 Sep 2026
- **Updated:** 22 Sep 2026
- **Also known as:** GHSA-25jc-v56j-jxq8

## What is CVE-2026-18458?

CVE-2026-18458 is a medium-severity memory corruption vulnerability in RTI Connext Professional, published on 22 Sep 2026. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

Out-of-bounds Read, Function Call With Incorrect Number of Arguments, Access of Resource Using Incompatible Type ('Type Confusion') vulnerability in RTI Connext Professional (Core Libraries) allows Overread Buffers. This issue affects Connext Professional: from 7.4.0 before 7.7.0.1, from 7.3.0 before 7.3.1.6, from 6.1.2.21 before 6.1.*.

Weakness: CWE-843 (Access of Resource Using Incompatible Type), CWE-685 (Function Call With Incorrect Number of Arguments), CWE-125 (Out-of-bounds Read)

## Which versions are affected by CVE-2026-18458?


## How do I fix CVE-2026-18458?

No fix has been published for CVE-2026-18458 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-18458 being exploited?

There is no known exploitation of CVE-2026-18458 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-18458 and fix it if it is affected.

What it is: CVE-2026-18458 is a medium-severity memory corruption vulnerability in RTI Connext Professional, published on 22 Sep 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2026-18458 in the wild and no public exploit code.

Affected product: RTI Connext Professional. No package-level version data is available, so check the vendor advisory linked from the reference page.

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2026-18458/ (Markdown: https://insights.sbomify.com/CVE-2026-18458/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-18458
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-18458
- OSV: https://osv.dev/vulnerability/CVE-2026-18458

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-18458/
Summaries are generated and may contain mistakes; the official description above is the record.