Invalid free of a stack buffer in libIEC61850 report sending
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- None
- Attack complexity
- Low
- Impact type
- —
- Confidentiality · integrity · availability
- None · None · Low
- Fix status
- Fixed
Attack profile from CVSS 3.1 · CNA. Fix status from CNA.
Summary
libIEC61850 before 1.6.2 is affected. The Reporting_RCBWriteAccessHandler accepts an RptID longer than 129 bytes in the report control block write path. When a GI request makes sendNextReportEntrySegment serialize the report, the stack-backed rptIdBuf[130] is passed to MmsValue_setVisibleString, whose resize path frees it as if it were heap memory (CWE-763). A remote client can crash the server by writing an oversized RptID and then generating a report.
Written with Claude Haiku 5.5 from the sources below · 2026-10-28
Description from the CNA
libIEC61850 is an open-source implementation of IEC 61850 client and server protocols including MMS, GOOSE, Sampled Values, and R-Session. Prior to 1.6.2, Reporting_RCBWriteAccessHandler accepts an RptID longer than 129 bytes in the report-control-block write path. When GI later causes sendNextReportEntrySegment to serialize the report, the function wraps rptIdBuf[130] as a temporary MmsValue and passes it to MmsValue_setVisibleString. The setter's resize path frees the stack-backed buffer, allowing a remote client to trigger an invalid free and server crash by writing the oversized RptID and then generating a report. This issue is fixed in version 1.6.2.
Why it matters now
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- Poc
- Automatable
- Yes
- Technical impact
- Partial
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| MZ Automation | libiec61850 | before 1.6.2 | 1.6.2 | Patch available | CNA |
- libiec61850 VendorMZ Automation Affected before 1.6.2 Fixed in 1.6.2 Patch available CNA
CPE names Threatist (inferred) · 1
Inferred from how NVD named this product before; not given by a source.
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:a:mz-automation:libiec61850:*:*:*:*:*:*:*:* | — | — | MZ Automation |
- cpe:2.3:a:mz-automation:libiec61850:*:*:*:*:*:*:*:* Versions — — ·MZ Automation
Remediation
Upgrade libIEC61850 to version 1.6.2, which fixes this issue.
Written with Claude Haiku 5.5 from the sources below · 2026-10-28
- Fix · CNA libiec61850 (mz-automation) Fixed in 1.6.2
Timeline
- 2026-10-16 Threatist record created from CVE-2026-68908
- 2026-10-16 CISA SSVC decision points changed
- 2026-10-16 Priority changed: LOW → MEDIUM
References
More MZ Automation vulnerabilities
- TI-2026-75355 Infinite loop and out-of-bounds read in libIEC61850 ACSE parsing CVSS 4.0HIGH 8.7
- TI-2026-75345 Remote NULL dereference in libIEC61850 MMS Read crashes servers CVSS 3.1HIGH 7.5
- TI-2026-75344 Remote information disclosure in libIEC61850 MMS file service CVSS 3.1HIGH 7.5
- TI-2024-18824 In mz-automation libiec61850 v1.4.0, a NULL Pointer Dereference was detected in the… CVSS 3.1HIGH 7.5
- TI-2022-05561 Infinite loop in MZ Automation libiec61850 CVSS 3.1HIGH 7.5
- TI-2026-45011 MZ Automation lib60870 Out-of-bounds Read CVSS 4.0MEDIUM 6.9
Sources
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences