Quick answer
Direct answer
Risk scores
| CVSS metric | What it means |
|---|---|
| Attack vector (AV:N) | Network: reachable remotely |
| Attack complexity (AC:L) | Low complexity |
| Attack requirements (AT:N) | No attack requirements |
| Privileges required (PR:N) | No privileges required |
| User interaction (UI:N) | No user interaction |
| Confidentiality (VC:H) | High confidentiality impact |
| Integrity (VI:N) | No integrity impact |
| Availability (VA:H) | High availability impact |
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/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
About Rti Connext Professional
CVE-2026-4374 affects Rti Connext Professional, a product from Rti. Before acting, confirm where Rti Connext Professional runs in your estate, who owns it and whether it is reachable from the internet, because exposure decides real risk more than the score alone.
What the flaw is
In plain terms: Improper Restriction of XML External Entity Reference vulnerability in RTI Connext Professional (Recording Service,Routing Service,Queueing Service,Cloud Discovery Service,Observability Collector) allows Serialized Data External Linking, Data Serialization External Entities Blowup. This issue affects Connext Professional: from 7.4.0 before 7.7.0, from 7.0.0 before 7.3.1.1, from 6.1.0 before 6.1.2.34, from 6.0.0 before 6.0.*, from 5.3.0 before 5.3.*.
The weakness class is XML External Entity. XML parsing can be abused to read files or reach internal systems.
Based on its CVSS vector, the flaw can be reached over the network, needs no login, and needs no user interaction. Apply the vendor fix and confirm exposure on internet facing and business critical assets first.
Affected versions and timeline
| Field | Detail |
|---|---|
| Product | Rti Connext Professional |
| Affected versions | Connext Professional from 5.3.0 up to and including 5.3.1.45; Connext Professional from 6.0.0 up to and including 6.0.1.40; Connext Professional from 6.1.0 up to and including 6.1.2.27; Connext Professional from 7.0.0 before 7.3.1.1; Connext Professional from 7.4.0 before 7.7.0 |
| Published | Apr 1, 2026 |
| Last modified | Sep 22, 2026 |
| Added to CISA KEV | Not listed |
| Assigning CNA | 3f572a00-62e2-4423-959a-7ea25eff1638 |
How to detect it
- Inventory every instance of Rti Connext Professional and record the running version against the affected range above.
- Check external attack surface scans for internet facing instances of the component.
- Review logs on affected systems for unusual requests, errors or new processes around the vulnerable function.
- Confirm with an authenticated vulnerability scan once your scanner has a check for this CVE.
How to fix it
- Apply the fixed version of Rti Connext Professional named in the vendor advisory.
- If patching must wait, restrict network access to the affected service and put it behind authentication or a web application firewall rule.
- Rescan after the change to prove the exposure is gone, then close the ticket.
CTEM action plan
| CTEM stage | What to do for this CVE |
|---|---|
| Scope | Add every business service that depends on Rti Connext Professional to the current CTEM cycle. |
| Discover | Find all instances, including shadow and cloud deployments, and record versions and exposure. |
| Prioritize | Rank using EPSS and CVSS together with asset exposure and business impact. |
| Validate | Confirm the flaw is reachable and exploitable in your environment and that compensating controls work. |
| Mobilize | Assign the fix to the asset owner with a due date matched to the priority, then verify closure. |
CWE References
- CWE-611: XML External Entity More CVEs with this weakness
Technical References
Frequently asked questions
Related CVEs
Out-of-bounds Read vulnerability in RTI Connext Professional (Core Libraries) allows Overread Buffers. This issue affects Connext Professional: from 7.4.0 before 7.7.0, from 7.0.0 before 7.3.1.3, 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 5.0.0 before 5.1.*.
Integer Underflow (Wrap or Wraparound) vulnerability in RTI Connext Micro (Core Libraries) allows Overread Buffers. This issue affects Connext Micro: from 4.0.0 before 4.3.0.
Out-of-bounds Read vulnerability in RTI Connext Micro (Core Libraries) allows Overread Buffers. This issue affects Connext Micro: from 4.0.0 before 4.3.0, from 2.4.5 before 2.4.*.
Heap-based Buffer Overflow vulnerability in RTI Connext Professional (Core Libraries) allows Overflow Variables and Tags. This issue affects Connext Professional: from 7.4.0 before 7.7.0, from 7.0.0 before 7.3.1.3, 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 5.0.0 before 5.1.*.
Improper Restriction of XML External Entity Reference vulnerability in RTI Connext Professional (Core Libraries) allows Serialized Data External Linking. This issue affects Connext Professional: from 7.4.0 before 7.7.0, from 7.0.0 before 7.3.1.1, 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 4.3x before 5.1.*.
Apache CXF's EndpointReferenceUtils and W3CMultiSchemaFactory classes construct a SAXParserFactory without the necessary JAXP hardening configurations, enabling out-of-band (OOB) external entity resolution. Users are recommended to upgrade to versions 4.2.2 or 4.1.7 or 3.6.12, which fix this issue.
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