Cyber Resilience

CVE-2026-4374

XXE in Rti Connext Professional 5.3.0 – 5.3.1.45

XXE
Published
01 April 2026
Modified
22 September 2026
Patch / advisory
View advisory
CVSS Score v4 8.8
Click a component to see what it means
Raw vectorCVSS: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
EPSS Score 0.0024 15th percentile
Risk Priority 43 floored blend · peak EPSS

CVSS and EPSS are reproduced from their sources (NVD, FIRST EPSS). Risk Priority is our own derived reading, not an NVD score.

Summary

CVE-2026-4374 is a high-severity Improper Restriction of XML External Entity Reference (CWE-611) vulnerability in Rti Connext Professional. Its CVSS base score is 8.8 (High).

Operationally, exploitation aligns with the MITRE ATT&CK technique Data from Local System (T1005); ranked at the 15th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.

The strongest mitigations our analysis identified map to CM-6 (Configuration Settings) and SA-11 (Developer Testing and Evaluation) — see the control section below for these in your framework.

Deeper analysis AI-assisted summary

Synthesised by an AI model from the NVD description and linked references — a reading aid, not an authoritative source.

CVE-2026-4374 is an Improper Restriction of XML External Entity Reference vulnerability (CWE-611) in RTI Connext Professional, affecting the Routing Service, Observability Collector, Recording Service, Queueing Service, and Cloud Discovery Service. The issue enables Serialized Data External Linking and Data Serialization flaws. It was published on 2026-04-01 and carries a CVSS v3.1 base score of 9.1 (AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H).

An unauthenticated remote attacker can exploit this vulnerability over the network with low attack complexity and without requiring user interaction. Successful exploitation can result in high impacts to confidentiality and availability, allowing unauthorized access to sensitive data and disruption of service.

Mitigation guidance and patches are detailed in the RTI vulnerability advisory at https://www.rti.com/vulnerabilities/#cve-2026-4374.

OWASP Top 10 for Web (2025)

A02:2025 Security Misconfiguration

EU & UK References

Vulnerability Data

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…

more

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.*.

CWE(s)
CWE-611

Related Threats

MITRE ATT&CK Enterprise Techniques

T1005 Data from Local System Collection
Adversaries may search local system sources, such as file systems, configuration files, local databases, virtual machine files, or process memory, to find files of interest and sensitive data prior to Exfiltration.
attack.mitre.org →
T1190 Exploit Public-Facing Application Initial Access
Adversaries may attempt to exploit a weakness in an Internet-facing host or system to initially access a network.
attack.mitre.org →
T1213 Data from Information Repositories Collection
Adversaries may leverage information repositories to mine valuable information.
attack.mitre.org →
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2025-14543Same product: Rti Connext Professional
CVE-2024-52057Same product: Rti Connext Professional
CVE-2025-10450Same product: Rti Connext Professional
CVE-2026-2675Same product: Rti Connext Professional
CVE-2026-30799Same product: Rti Connext Professional
CVE-2025-4582Same product: Rti Connext Professional
CVE-2026-2394Same product: Rti Connext Professional
CVE-2025-1253Same product: Rti Connext Professional
CVE-2026-2467Same product: Rti Connext Professional
CVE-2024-25724Same product: Rti Connext Professional

Affected Assets

rti
connext professional
5.3.0 — 5.3.1.45 · 6.0.0 — 6.0.1.40 · 6.1.0 — 6.1.2.27

Mitigating Controls

Control response

Prevent
Stop it (NIST 800-53)

—

Detect
Catch it (NIST detect / respond)

—

Harden
Shrink the surface (DISA STIG)

—

Validate
Prove the fix (OWASP ASVS)
  • V1.5.1
  • V15.3.2

Mitigating Controls (NIST 800-53 r5) AI

CM-6 Configuration Settings good match

Secure configuration settings can disable external entity processing in XML parsers.

SA-11 Developer Testing and Evaluation good match

Developer testing can discover XXE flaws through targeted XML parsing tests.

SI-10 Information Input Validation good match

Input validation can reject or sanitize XML containing external entity references.

Mitigating Controls (NIST CSF 2.0) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.

ID.RA-01 partial match
prevents

Vulnerability scanning can discover XXE flaws but does not prevent their introduction in code.

PR.PS-01 partial match
prevents

Hardened XML parser configurations directly disable external entity resolution.

PR.PS-02 partial match
prevents

Patching eliminates XXE-vulnerable parser versions but is only one aspect of software maintenance.

PR.PS-06 partial match
prevents

Secure SDLC practices include input validation and safe XML parser configuration that prevent XXE.

Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.

A.8.25 Secure development life cycle partial match
prevents

Secure development life cycle mandates input validation and entity handling that directly prevents XXE.

A.8.26 Application security requirements partial match
prevents

Application security requirements explicitly call for disabling external entity processing in XML parsers.

A.8.27 Secure system architecture and engineering principles partial match
prevents

Secure architecture principles include safe parser configuration that mitigates external entity risks.

A.8.28 Secure coding partial match
prevents

Secure coding standards require disabling DTDs and external entities in XML processing.

A.8.29 Security testing in development and acceptance partial match
finds

Security testing in development catches XXE via static analysis and dynamic XML fuzzing.

A.8.8 Management of technical vulnerabilities partial match
finds

Vulnerability management identifies and patches XML libraries with unsafe default entity settings.

References