diff --git a/textproc/libxml2/Makefile b/textproc/libxml2/Makefile
index 366bb9f46f5e..749bc604fe4a 100644
--- a/textproc/libxml2/Makefile
+++ b/textproc/libxml2/Makefile
@@ -1,76 +1,76 @@
 # Created by: Yukihiro Nakai <Nakai@technologist.com>
 
 PORTNAME=	libxml2
 DISTVERSION=	2.9.10
-PORTREVISION?=	3
+PORTREVISION?=	4
 CATEGORIES?=	textproc gnome
 MASTER_SITES=	http://xmlsoft.org/sources/
 DIST_SUBDIR=	gnome2
 
 MAINTAINER?=	desktop@FreeBSD.org
 COMMENT?=	XML parser library for GNOME
 
 LICENSE=	MIT TRIO
 LICENSE_COMB=	multi
 LICENSE_NAME_TRIO=	Trio License
 LICENSE_FILE_MIT=	${WRKSRC}/COPYING
 LICENSE_FILE_TRIO=	${FILESDIR}/LICENSE.TRIO
 LICENSE_PERMS_TRIO=	dist-mirror dist-sell pkg-mirror pkg-sell auto-accept
 
 GNU_CONFIGURE=	yes
 USES+=		compiler cpe iconv libtool pathfix pkgconfig shebangfix
 CPE_VENDOR=	xmlsoft
 USE_LDCONFIG=	yes
 CONFIGURE_ARGS?=--with-iconv=${ICONV_PREFIX} \
 		--with-html-dir=${PREFIX}/share/doc \
 		--with-html-subdir=${PORTNAME} \
 		--without-icu \
 		--with-lzma=/usr \
 		--without-python
 INSTALL_TARGET=	install-strip
 SHEBANG_FILES=	*.py */*.py */*/*.py
 
 PLIST_SUB+=	LIBVERSION=${PORTVERSION}
 
 .if !defined(MASTERDIR)
 
 OPTIONS_DEFINE=	SCHEMA VALIDATION THREADS MEM_DEBUG XMLLINT_HIST THREAD_ALLOC
 OPTIONS_DEFAULT=SCHEMA VALIDATION THREADS
 SCHEMA_DESC=	XML schema support
 SCHEMA_CONFIGURE_WITH=	schemas
 VALIDATION_DESC=	Validation support
 VALIDATION_CONFIGURE_OFF=	--without-valid
 THREADS_DESC=	Threads support
 THREADS_CONFIGURE_WITH=	threads
 MEM_DEBUG_DESC=	Memory debugging (DEVELOPERS ONLY!)
 MEM_DEBUG_CONFIGURE_WITH=	mem-debug
 XMLLINT_HIST_DESC=	History for xmllint
 XMLLINT_HIST_CONFIGURE_WITH=	history
 THREAD_ALLOC_DESC=	Per-thread memory (DEVELOPERS ONLY!)
 THREAD_ALLOC_CONFIGURE_WITH=	thread-alloc
 
 .endif # !defined(MASTERDIR)
 
 .if !defined(MASTERDIR)
 post-install:
 	@${RM} -r ${STAGEDIR}${PREFIX}/share/gtk-doc
 .endif
 
 .include <bsd.port.pre.mk>
 
 post-patch:
 .for d in . doc doc/devhelp doc/examples
 	@${REINPLACE_CMD} -e '/^install-data-am:/ s|install-data-local||' \
 		${WRKSRC}/${d}/Makefile.in
 .endfor
 .for f in catalog.c xmlcatalog.c xmllint.c doc/xmllint.1
 	@${REINPLACE_CMD} -e \
 		's|/etc/xml/catalog|${LOCALBASE}/share/xml/catalog|g; \
 		 s|/etc/sgml/catalog|${LOCALBASE}/share/sgml/catalog|g' \
 		${WRKSRC}/${f}
 .endfor
 .if ${CHOSEN_COMPILER_TYPE} == gcc
 	@${REINPLACE_CMD} -e 's/ -Wno-array-bounds//' ${WRKSRC}/configure
 .endif
 
 .include <bsd.port.post.mk>
diff --git a/textproc/libxml2/files/patch-CVE-2021-3541 b/textproc/libxml2/files/patch-CVE-2021-3541
new file mode 100644
index 000000000000..3ba64fa1d967
--- /dev/null
+++ b/textproc/libxml2/files/patch-CVE-2021-3541
@@ -0,0 +1,67 @@
+From 8598060bacada41a0eb09d95c97744ff4e428f8e Mon Sep 17 00:00:00 2001
+From: Daniel Veillard <veillard@redhat.com>
+Date: Thu, 13 May 2021 14:55:12 +0200
+Subject: [PATCH] Patch for security issue CVE-2021-3541
+
+This is relapted to parameter entities expansion and following
+the line of the billion laugh attack. Somehow in that path the
+counting of parameters was missed and the normal algorithm based
+on entities "density" was useless.
+---
+ parser.c | 26 ++++++++++++++++++++++++++
+ 1 file changed, 26 insertions(+)
+
+diff --git parser.c parser.c
+index f5e5e169..c9312fa4 100644
+--- parser.c
++++ parser.c
+@@ -140,6 +140,7 @@ xmlParserEntityCheck(xmlParserCtxtPtr ctxt, size_t size,
+                      xmlEntityPtr ent, size_t replacement)
+ {
+     size_t consumed = 0;
++    int i;
+ 
+     if ((ctxt == NULL) || (ctxt->options & XML_PARSE_HUGE))
+         return (0);
+@@ -177,6 +178,28 @@ xmlParserEntityCheck(xmlParserCtxtPtr ctxt, size_t size,
+ 	    rep = NULL;
+ 	}
+     }
++
++    /*
++     * Prevent entity exponential check, not just replacement while
++     * parsing the DTD
++     * The check is potentially costly so do that only once in a thousand
++     */
++    if ((ctxt->instate == XML_PARSER_DTD) && (ctxt->nbentities > 10000) &&
++        (ctxt->nbentities % 1024 == 0)) {
++	for (i = 0;i < ctxt->inputNr;i++) {
++	    consumed += ctxt->inputTab[i]->consumed +
++	               (ctxt->inputTab[i]->cur - ctxt->inputTab[i]->base);
++	}
++	if (ctxt->nbentities > consumed * XML_PARSER_NON_LINEAR) {
++	    xmlFatalErr(ctxt, XML_ERR_ENTITY_LOOP, NULL);
++	    ctxt->instate = XML_PARSER_EOF;
++	    return (1);
++	}
++	consumed = 0;
++    }
++
++
++
+     if (replacement != 0) {
+ 	if (replacement < XML_MAX_TEXT_LENGTH)
+ 	    return(0);
+@@ -7963,6 +7986,9 @@ xmlParsePEReference(xmlParserCtxtPtr ctxt)
+             xmlChar start[4];
+             xmlCharEncoding enc;
+ 
++	    if (xmlParserEntityCheck(ctxt, 0, entity, 0))
++	        return;
++
+ 	    if ((entity->etype == XML_EXTERNAL_PARAMETER_ENTITY) &&
+ 	        ((ctxt->options & XML_PARSE_NOENT) == 0) &&
+ 		((ctxt->options & XML_PARSE_DTDVALID) == 0) &&
+-- 
+2.31.1
+