new file mode 100644
@@ -0,0 +1,51 @@
+From 43aa106301639f2afddf11302d25e84c5482e26c Mon Sep 17 00:00:00 2001
+From: Michael Zillgith <michael.zillgith@mz-automation.de>
+Date: Tue, 16 Jun 2026 19:24:12 +0100
+Subject: [PATCH] - MMS server: fixed - oversized RptID written to RCB can
+ trigger invalid free when reports are sent later
+ (LIB61850-561)(GHSA-7qg8-hm25-rv5v)
+
+(cherry picked from commit 5b2a69f44256b8548927d8afdd7ac5f5381abe1e)
+
+CVE: CVE-2026-18582
+Upstream-Status: Backport [https://github.com/mz-automation/libiec61850/commit/5b2a69f44256b8548927d8afdd7ac5f5381abe1e]
+
+Signed-off-by: Ankur Tyagi <ankur.tyagi85@gmail.com>
+---
+ src/iec61850/server/mms_mapping/reporting.c | 9 +++++++--
+ 1 file changed, 7 insertions(+), 2 deletions(-)
+
+diff --git a/src/iec61850/server/mms_mapping/reporting.c b/src/iec61850/server/mms_mapping/reporting.c
+index 2a230c28..a44f0583 100644
+--- a/src/iec61850/server/mms_mapping/reporting.c
++++ b/src/iec61850/server/mms_mapping/reporting.c
+@@ -557,7 +557,6 @@ updateSingleTrackingValue(MmsMapping* self, ReportControl* rc, const char* name,
+ attributeToUpdate = trkInst->resv;
+ else if (!strcmp(name, "DatSet"))
+ {
+-
+ char datSet[130];
+ const char* datSetStr = MmsValue_toString(newValue);
+
+@@ -2664,6 +2663,12 @@ Reporting_RCBWriteAccessHandler(MmsMapping* self, ReportControl* rc, const char*
+ goto exit_function;
+ }
+
++ if (MmsValue_getStringSize(value) > 129)
++ {
++ retVal = DATA_ACCESS_ERROR_OBJECT_VALUE_INVALID;
++ goto exit_function;
++ }
++
+ #if (CONFIG_MMS_THREADLESS_STACK != 1)
+ Semaphore_wait(rc->rcbValuesLock);
+ #endif
+@@ -3677,7 +3682,7 @@ sendNextReportEntrySegment(ReportControl* self)
+
+ const char* rptIdStr = MmsValue_toString(rptIdFromRcb);
+
+- if (rptIdStr[0] == 0)
++ if (rptIdStr[0] == 0 || MmsValue_getStringSize(rptIdFromRcb) > 129)
+ {
+ /* use default rptId when RptID is empty in RCB */
+ updateWithDefaultRptId(self, &rptId);
@@ -17,6 +17,7 @@ SRCREV = "a13961110b8238d2d8ea577c1fb7592ba3017ad8"
SRC_URI = "git://github.com/mz-automation/${BPN}.git;branch=v1.6;protocol=https;tag=v${PV} \
file://0001-pyiec61850-Use-CMAKE_INSTALL_LIBDIR-from-GNUInstallD.patch \
+ file://CVE-2026-18582.patch \
"