Vulnerability · Published Oct 16, 2026 · Assigned by GitHub_M
CVE-2026-68908libIEC61850: Oversized RptID can trigger invalid free of a stack-backed visible string in the report send path
Medium 5.3
In plain English
A medium-severity security flaw in libiec61850 from mz-automation. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.5% (higher than 39% of all known vulnerabilities).
Official description
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.
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| mz-automation | libiec61850 | < 1.6.2 |
Weakness: CWE-590, CWE-664, CWE-763 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L