PatchSiren cyber security CVE debrief
CVE-2026-50103 MZ Automation CVE debrief
A NULL pointer dereference vulnerability exists in the L2 GOOSE and R-GOOSE shared parser of MZ Automation libIEC61850. This issue may allow a network-adjacent attacker to crash a subscribing application by sending a crafted GOOSE frame containing a malformed TLV value. The vulnerability has a CVSS score of 6.5 and a severity of MEDIUM. Organizations should prioritize updating to the latest build to mitigate this vulnerability. Evidence from official records indicates that defenders should verify affected product deployments, review official advisories, and plan vendor-supported updates or mitigations. The CVE record and CISA CSAF advisory provide details on the vulnerability, but additional verification is recommended to ensure the accuracy of the information.
- Vendor
- MZ Automation
- Product
- libIEC61850
- CVSS
- MEDIUM 6.5
- CISA KEV
- Not listed in stored evidence
- Original CVE published
- 2026-07-23
- Original CVE updated
- 2026-07-23
- Advisory published
- 2026-07-23
- Advisory updated
- 2026-07-23
Who should care
Organizations using MZ Automation libIEC61850 in their industrial control systems should prioritize updating to the latest build to mitigate this vulnerability. This includes operators of affected systems, platform administrators, vulnerability management teams, and security teams responsible for ensuring the security and integrity of their industrial control systems.
Technical summary
The vulnerability exists in the L2 GOOSE and R-GOOSE shared parser of MZ Automation libIEC61850. A network-adjacent attacker may exploit this issue by sending a crafted GOOSE frame containing a malformed TLV value, potentially causing a subscribing application to crash. This issue has a CVSS score of 6.5 and a severity of MEDIUM. Organizations should prioritize updating to the latest build to mitigate this vulnerability.
Defensive priority
Medium priority given the potential for denial of service and the availability of a vendor fix.
Recommended defensive actions
- Update to the latest build of libIEC61850 as recommended by MZ Automation
- Implement network segmentation to limit the attack surface
- Monitor for suspicious network activity
- Review and update incident response plans
- Confirm whether affected product deployments exist in managed environments and assign an owner for follow-up
- Review compensating controls for exposed systems while remediation is scheduled and verified
- Track exceptions, retest remediated assets, and close the item only after evidence is documented
Evidence notes
The CVE record and CISA CSAF advisory provide details on the vulnerability. Evidence is based on official records from CVE.org and NVD. The vulnerability exists in the L2 GOOSE and R-GOOSE shared parser of MZ Automation libIEC61850, which may allow a network-adjacent attacker to crash a subscribing application by sending a crafted GOOSE frame containing a malformed TLV value. Defenders should verify affected product deployments, review official advisories, and plan vendor-supported updates or mitigations.
Sources and references
Verified primary and authoritative sources
-
CVE-2026-50103 CVE Program record
Publisher, destination, and source semantics verified
URL: https://www.cve.org/CVERecord?id=CVE-2026-50103
CVE Program - Official CVE Program record with source-provided CVE metadata.
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CVE-2026-50103 NVD vulnerability detail
Publisher, destination, and source semantics verified
URL: https://nvd.nist.gov/vuln/detail/CVE-2026-50103
NIST National Vulnerability Database - Official NIST NVD detail page and source-specific vulnerability assessment.
Supplemental references
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Source item URL
Unverified legacy reference
URL: https://raw.githubusercontent.com/cisagov/CSAF/develop/csaf_files/OT/white/2026/icsa-26-204-06.json
cisa_csaf
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Source reference
Unverified legacy reference
URL: https://www.cisa.gov/news-events/ics-advisories/icsa-26-204-06
Reference
-
Source reference
Unverified legacy reference
URL: https://www.cisa.gov/uscert/ics/alerts/ICS-ALERT-10-301-01
Reference
-
Source reference
Unverified legacy reference
URL: https://www.cisa.gov/resources-tools/resources/ics-recommended-practices
Reference
-
Source reference
Unverified legacy reference
URL: https://www.cisa.gov/sites/default/files/publications/Cybersecurity_Best_Practices_for_Industrial_Control_Systems.pdf
Reference
-
Source reference
Unverified legacy reference
URL: https://www.cisa.gov/topics/industrial-control-systems
Reference
-
Source reference
Unverified legacy reference
URL: https://www.cisa.gov/uscert/sites/default/files/publications/emailscams0905.pdf
Reference
-
Source reference
Unverified legacy reference
URL: https://www.cisa.gov/uscert/ncas/tips/ST04-014
Reference
Methodology and review provenance
AI-assisted synthesis based on stored public vulnerability evidence. System validation, approval state, and publication status do not by themselves establish human review of this revision. PatchSiren helps prioritize defensive review and does not prove exposure or remediation on any system.