diff --git a/meta/recipes-core/libxml/libxml2/CVE-2026-86143.patch b/meta/recipes-core/libxml/libxml2/CVE-2026-86143.patch
new file mode 100644
index 0000000000..e3f1197e2d
--- /dev/null
+++ b/meta/recipes-core/libxml/libxml2/CVE-2026-86143.patch
@@ -0,0 +1,61 @@
+From 90f293ba74d28b1d570920382e707586f68ebf35 Mon Sep 17 00:00:00 2001
+From: Daniel Garcia Moreno <daniel.garcia@suse.com>
+Date: Mon, 4 May 2026 09:54:34 +0200
+Subject: [PATCH] xmlIO: Check for int overflow before calling writecallback
+
+Fix https://gitlab.gnome.org/GNOME/libxml2/-/work_items/1111
+
+Upstream-Status: Backport [https://gitlab.gnome.org/GNOME/libxml2/-/commit/90f293ba74d28b1d570920382e707586f68ebf35]
+CVE: CVE-2026-86143
+Signed-off-by: Siddharth Doshi <sdoshi@mvista.com>
+---
+ xmlIO.c | 19 +++++++++++++++++--
+ 1 file changed, 17 insertions(+), 2 deletions(-)
+
+diff --git a/xmlIO.c b/xmlIO.c
+index 95d2715..a117228 100644
+--- a/xmlIO.c
++++ b/xmlIO.c
+@@ -3378,6 +3378,11 @@ xmlOutputBufferWrite(xmlOutputBufferPtr out, int len, const char *buf) {
+             if ((nbchars < MINLEN) && (len <= 0))
+                 goto done;
+ 
++            if (nbchars >= INT_MAX) {
++                out->error = XML_ERR_INTERNAL_ERROR;
++                return(-1);
++            }
++
+ 	    /*
+ 	     * second write the stuff to the I/O channel
+ 	     */
+@@ -3667,15 +3672,25 @@ xmlOutputBufferFlush(xmlOutputBufferPtr out) {
+      */
+     if ((out->conv != NULL) && (out->encoder != NULL) &&
+ 	(out->writecallback != NULL)) {
++        size_t bufsize = xmlBufUse(out->conv);
++        if (bufsize >= INT_MAX) {
++            out->error = XML_ERR_INTERNAL_ERROR;
++            return(-1);
++        }
+ 	ret = out->writecallback(out->context,
+                                  (const char *)xmlBufContent(out->conv),
+-                                 xmlBufUse(out->conv));
++                                 bufsize);
+ 	if (ret >= 0)
+ 	    xmlBufShrink(out->conv, ret);
+     } else if (out->writecallback != NULL) {
++        size_t bufsize = xmlBufUse(out->buffer);
++        if (bufsize >= INT_MAX) {
++            out->error = XML_ERR_INTERNAL_ERROR;
++            return(-1);
++        }
+ 	ret = out->writecallback(out->context,
+                                  (const char *)xmlBufContent(out->buffer),
+-                                 xmlBufUse(out->buffer));
++                                 bufsize);
+ 	if (ret >= 0)
+ 	    xmlBufShrink(out->buffer, ret);
+     }
+-- 
+2.34.1
+
diff --git a/meta/recipes-core/libxml/libxml2_2.12.10.bb b/meta/recipes-core/libxml/libxml2_2.12.10.bb
index 2869aa46ac..a15de5d353 100644
--- a/meta/recipes-core/libxml/libxml2_2.12.10.bb
+++ b/meta/recipes-core/libxml/libxml2_2.12.10.bb
@@ -36,6 +36,7 @@ SRC_URI += "http://www.w3.org/XML/Test/xmlts20130923.tar;subdir=${BP};name=testt
            file://CVE-2026-86138.patch \
            file://CVE-2026-86140.patch \
            file://CVE-2026-86141.patch \
+           file://CVE-2026-86143.patch \
            "
 
 SRC_URI[archive.sha256sum] = "c3d8c0c34aa39098f66576fe51969db12a5100b956233dc56506f7a8679be995"