diff --git a/graphics/libmng/Makefile b/graphics/libmng/Makefile
index 80205d515e38..60327a485767 100644
--- a/graphics/libmng/Makefile
+++ b/graphics/libmng/Makefile
@@ -1,26 +1,20 @@
 PORTNAME=	libmng
-PORTVERSION=	1.0.10
-PORTREVISION=	4
+DISTVERSION=	2.0.3
 CATEGORIES=	graphics
-MASTER_SITES=	SF/${PORTNAME}/${PORTNAME}-devel/${PORTVERSION} \
-		http://www.libmng.com/download/
+MASTER_SITES=	SF/${PORTNAME}/${PORTNAME}-devel/${DISTVERSION}
 
 MAINTAINER=	mi@aldan.algebra.com
 COMMENT=	Multiple-image Network Graphics (MNG) reference library
-WWW=		https://www.libmng.com/
+WWW=		https://sourceforge.net/projects/libmng/
 
-LIB_DEPENDS=	liblcms.so:graphics/lcms
+LIB_DEPENDS=	liblcms2.so:graphics/lcms2
 
-OPTIONS_DEFINE=	MNG_OPTIMIZE
-MNG_OPTIMIZE_DESC=	Use vendor's new optimization flags
-
-MAKEFILE=	${FILESDIR}/Makefile.bsd
-
-USES=		jpeg uidfix
+USES=		cmake jpeg localbase:ldflags tar:xz
 USE_LDCONFIG=	yes
 
-MNG_OPTIMIZE_MAKE_ARGS=	WITH_MNG_OPTIMIZE=true
-MNG_OPTIMIZE_MAKE_ARGS_OFF=	WITH_MNG_OPTIMIZE=off
+CMAKE_ARGS=	-DLCMS2_INCLUDE_DIR=${PREFIX}/include \
+		-DMNG_INSTALL_PACKAGE_DIR=${PREFIX}/lib/cmake/libmng \
+		-DMNG_INSTALL_PKGCONFIG_DIR=${PREFIX}/libdata/pkgconfig
 
 post-install:
 	cd ${WRKSRC}/doc/man && ${INSTALL_MAN} libmng.3 ${STAGEDIR}${PREFIX}/man/man3 \
diff --git a/graphics/libmng/distinfo b/graphics/libmng/distinfo
index 7a8befb1f5db..bde296665112 100644
--- a/graphics/libmng/distinfo
+++ b/graphics/libmng/distinfo
@@ -1,2 +1,3 @@
-SHA256 (libmng-1.0.10.tar.gz) = 03a79dac9b9316d37227057614a248a946f997c4d1a3437fb569e9a63897f911
-SIZE (libmng-1.0.10.tar.gz) = 1093337
+TIMESTAMP = 1704743955
+SHA256 (libmng-2.0.3.tar.xz) = 4a462fdd48d4bc82c1d7a21106c8a18b62f8cc0042454323058e6da0dbb57dd3
+SIZE (libmng-2.0.3.tar.xz) = 951808
diff --git a/graphics/libmng/files/Makefile.bsd b/graphics/libmng/files/Makefile.bsd
deleted file mode 100644
index 865b974c0bd2..000000000000
--- a/graphics/libmng/files/Makefile.bsd
+++ /dev/null
@@ -1,22 +0,0 @@
-LIB=	mng
-LDADD=	-lm -L${LIBDIR} -lz -llcms -ljpeg
-
-MK_PROFILE=	no
-SHLIB_MAJOR?=	1
-SHLIB_MINOR?=	0
-
-SRCS!=		${MAKE} -f ${.CURDIR}/makefiles/makefile.unix -V SOURCES
-
-CFLAGS+=	-I${INCDIR}
-.if ${WITH_MNG_OPTIMIZE} == "true"
-.for f in CHUNKINITFREE OBJCLEANUP CHUNKASSIGN CHUNKREADER
-CFLAGS+=	-DMNG_OPTIMIZE_$f
-.endfor
-.endif
-
-INCS=		libmng.h libmng_conf.h libmng_types.h
-INCSDIR=	${LOCALBASE}/include
-INCDIR=		${INCSDIR}		# for pre-bsd.incs.mk API
-LIBDIR=		${LOCALBASE}/lib
-
-.include <bsd.lib.mk>
diff --git a/graphics/libmng/files/patch-CMakeLists.txt b/graphics/libmng/files/patch-CMakeLists.txt
new file mode 100644
index 000000000000..3c62ca644ca3
--- /dev/null
+++ b/graphics/libmng/files/patch-CMakeLists.txt
@@ -0,0 +1,26 @@
+--- CMakeLists.txt.orig	2012-07-29 19:28:11 UTC
++++ CMakeLists.txt
+@@ -52,15 +52,15 @@ IF(NOT MNG_INSTALL_LIB_DIR)
+ ENDIF(NOT MNG_INSTALL_BIN_DIR)
+ #
+ IF(NOT MNG_INSTALL_LIB_DIR)
+- IF(UNIX)
+-  IF(CMAKE_SIZEOF_VOID_P EQUAL "8")
+-   SET(MNG_INSTALL_LIB_DIR "lib64") 
+-  ELSE(CMAKE_SIZEOF_VOID_P EQUAL "8")
+-   SET(MNG_INSTALL_LIB_DIR "lib")
+-  ENDIF(CMAKE_SIZEOF_VOID_P EQUAL "8")
+- ELSE(UNIX)
++# IF(UNIX)
++#  IF(CMAKE_SIZEOF_VOID_P EQUAL "8")
++#   SET(MNG_INSTALL_LIB_DIR "lib64") 
++#  ELSE(CMAKE_SIZEOF_VOID_P EQUAL "8")
++#   SET(MNG_INSTALL_LIB_DIR "lib")
++#  ENDIF(CMAKE_SIZEOF_VOID_P EQUAL "8")
++# ELSE(UNIX)
+   SET(MNG_INSTALL_LIB_DIR "lib")
+- ENDIF(UNIX)
++# ENDIF(UNIX)
+ ENDIF(NOT MNG_INSTALL_LIB_DIR)
+ #
+ IF(NOT MNG_INSTALL_SHARE_DIR)
diff --git a/graphics/libmng/files/patch-chunk_descr.c b/graphics/libmng/files/patch-chunk_descr.c
new file mode 100644
index 000000000000..c4d6f9871f82
--- /dev/null
+++ b/graphics/libmng/files/patch-chunk_descr.c
@@ -0,0 +1,9 @@
+--- libmng_chunk_descr.c	2012-07-29 15:26:34.000000000 -0400
++++ libmng_chunk_descr.c	2024-01-08 14:32:15.916979000 -0500
+@@ -2751,5 +2751,5 @@
+       mng_get_chunkheader (MNG_UINT_sRGB, &chunk_srgb);
+                                        /* pretend it's an sRGB chunk then ! */
+-      iRetcode = mng_read_general (pData, &chunk_srgb, 1, (mng_ptr)"0", &pDummy);
++      iRetcode = mng_read_general (pData, &chunk_srgb, 1, (mng_ptr)"0", (void **)&pDummy);
+       if (iRetcode)                    /* on error bail out */
+         return iRetcode;
diff --git a/graphics/libmng/files/patch-conf b/graphics/libmng/files/patch-conf
deleted file mode 100644
index 2413a8b8bbfd..000000000000
--- a/graphics/libmng/files/patch-conf
+++ /dev/null
@@ -1,19 +0,0 @@
-+++ libmng_conf.h	Tue Oct 18 00:23:11 2005
-@@ -100,4 +100,8 @@
- #endif
- 
-+#ifdef PIC
-+#	define MNG_BUILD_SO
-+#endif
-+
- #ifndef MNG_SUPPORT_IJG6B
- #if defined(MNG_BUILD_SO) || defined(MNG_USE_SO) || defined(MNG_BUILD_DLL) || defined(MNG_USE_DLL)
-@@ -161,6 +165,6 @@
-    select MNG_APP_CMS */
- 
--#define MNG_GAMMA_ONLY
--/* #define MNG_FULL_CMS */
-+/* #define MNG_GAMMA_ONLY */
-+#define MNG_FULL_CMS
- /* #define MNG_APP_CMS */
-  
diff --git a/graphics/libmng/files/patch-filter.c b/graphics/libmng/files/patch-filter.c
new file mode 100644
index 000000000000..75eaf815b53b
--- /dev/null
+++ b/graphics/libmng/files/patch-filter.c
@@ -0,0 +1,13 @@
+--- libmng_filter.c	2012-07-29 15:26:34.000000000 -0400
++++ libmng_filter.c	2024-01-08 14:25:01.379756000 -0500
+@@ -207,7 +207,7 @@
+     iC  = (mng_uint32)*pPriorx_prev;
+     iP  = iA + iB - iC;
+-    iPa = abs (iP - iA);
+-    iPb = abs (iP - iB);
+-    iPc = abs (iP - iC);
++    iPa = iP > iA ? iP - iA : iA - iP;
++    iPb = iP > iB ? iP - iB : iB - iP;
++    iPc = iP > iC ? iP - iC : iC - iP;
+ 
+     if ((iPa <= iPb) && (iPa <= iPc))
diff --git a/graphics/libmng/files/patch-pixels.c b/graphics/libmng/files/patch-pixels.c
new file mode 100644
index 000000000000..a74b3653ba22
--- /dev/null
+++ b/graphics/libmng/files/patch-pixels.c
@@ -0,0 +1,128 @@
+This changes the behaviour to what appears to be the original intent...
+
+	-mi
+
+--- libmng_pixels.c	2012-07-29 15:26:34.000000000 -0400
++++ libmng_pixels.c	2024-01-08 14:21:18.664893000 -0500
+@@ -14669,5 +14669,5 @@
+ 
+     *pDstline     = (mng_uint8)(iW >> 8);
+-    *(pDstline+1) = (mng_uint8)(iW && 0xFF);
++    *(pDstline+1) = (mng_uint8)(iW & 0xFF);
+ 
+     pSrcline++;
+@@ -14787,5 +14787,5 @@
+ 
+     *pDstline     = (mng_uint8)(iW >> 8);
+-    *(pDstline+1) = (mng_uint8)(iW && 0xFF);
++    *(pDstline+1) = (mng_uint8)(iW & 0xFF);
+ 
+     pSrcline++;
+@@ -14908,5 +14908,5 @@
+     *(pDstline+2) = iB;
+     *(pDstline+4) = iB;
+-    iB            = (mng_uint8)(iW && 0xFF);
++    iB            = (mng_uint8)(iW & 0xFF);
+     *(pDstline+1) = iB;
+     *(pDstline+3) = iB;
+@@ -15042,5 +15042,5 @@
+     *(pDstline+2) = iB;
+     *(pDstline+4) = iB;
+-    iB            = (mng_uint8)(iW && 0xFF);
++    iB            = (mng_uint8)(iW & 0xFF);
+     *(pDstline+1) = iB;
+     *(pDstline+3) = iB;
+@@ -15126,7 +15126,7 @@
+ 
+     *pDstline     = (mng_uint8)(iW >> 8);
+-    *(pDstline+1) = (mng_uint8)(iW && 0xFF);
++    *(pDstline+1) = (mng_uint8)(iW & 0xFF);
+     *(pDstline+2) = (mng_uint8)(iA >> 8);
+-    *(pDstline+3) = (mng_uint8)(iA && 0xFF);
++    *(pDstline+3) = (mng_uint8)(iA & 0xFF);
+ 
+     pSrcline += 2;
+@@ -15210,10 +15210,10 @@
+     *(pDstline+2) = iB;
+     *(pDstline+4) = iB;
+-    iB            = (mng_uint8)(iW && 0xFF);
++    iB            = (mng_uint8)(iW & 0xFF);
+     *(pDstline+1) = iB;
+     *(pDstline+3) = iB;
+     *(pDstline+5) = iB;
+     *(pDstline+6) = (mng_uint8)(iA >> 8);
+-    *(pDstline+7) = (mng_uint8)(iA && 0xFF);
++    *(pDstline+7) = (mng_uint8)(iA & 0xFF);
+ 
+     pSrcline += 2;
+@@ -15297,9 +15297,9 @@
+ 
+     *pDstline     = (mng_uint8)(iR >> 8);
+-    *(pDstline+1) = (mng_uint8)(iR && 0xFF);
++    *(pDstline+1) = (mng_uint8)(iR & 0xFF);
+     *(pDstline+2) = (mng_uint8)(iG >> 8);
+-    *(pDstline+3) = (mng_uint8)(iG && 0xFF);
++    *(pDstline+3) = (mng_uint8)(iG & 0xFF);
+     *(pDstline+4) = (mng_uint8)(iB >> 8);
+-    *(pDstline+5) = (mng_uint8)(iB && 0xFF);
++    *(pDstline+5) = (mng_uint8)(iB & 0xFF);
+ 
+     pSrcline += 3;
+@@ -15402,9 +15402,9 @@
+ 
+     *pDstline     = (mng_uint8)(iRw >> 8);
+-    *(pDstline+1) = (mng_uint8)(iRw && 0xFF);
++    *(pDstline+1) = (mng_uint8)(iRw & 0xFF);
+     *(pDstline+2) = (mng_uint8)(iGw >> 8);
+-    *(pDstline+3) = (mng_uint8)(iGw && 0xFF);
++    *(pDstline+3) = (mng_uint8)(iGw & 0xFF);
+     *(pDstline+4) = (mng_uint8)(iBw >> 8);
+-    *(pDstline+5) = (mng_uint8)(iBw && 0xFF);
++    *(pDstline+5) = (mng_uint8)(iBw & 0xFF);
+ 
+     pSrcline += 3;
+@@ -15539,9 +15539,9 @@
+       iB              = ((mng_bitdepth_16)pData->fPromBitdepth) (pBuf->aPLTEentries [iN].iBlue);
+       *pDstline       = (mng_uint8)(iR >> 8);
+-      *(pDstline+1)   = (mng_uint8)(iR && 0xFF);
++      *(pDstline+1)   = (mng_uint8)(iR & 0xFF);
+       *(pDstline+2)   = (mng_uint8)(iG >> 8);
+-      *(pDstline+3)   = (mng_uint8)(iG && 0xFF);
++      *(pDstline+3)   = (mng_uint8)(iG & 0xFF);
+       *(pDstline+4)   = (mng_uint8)(iB >> 8);
+-      *(pDstline+5)   = (mng_uint8)(iB && 0xFF);
++      *(pDstline+5)   = (mng_uint8)(iB & 0xFF);
+     }
+ 
+@@ -15642,11 +15642,11 @@
+ 
+       *pDstline     = (mng_uint8)(iR >> 8);
+-      *(pDstline+1) = (mng_uint8)(iR && 0xFF);
++      *(pDstline+1) = (mng_uint8)(iR & 0xFF);
+       *(pDstline+2) = (mng_uint8)(iG >> 8);
+-      *(pDstline+3) = (mng_uint8)(iG && 0xFF);
++      *(pDstline+3) = (mng_uint8)(iG & 0xFF);
+       *(pDstline+4) = (mng_uint8)(iB >> 8);
+-      *(pDstline+5) = (mng_uint8)(iB && 0xFF);
++      *(pDstline+5) = (mng_uint8)(iB & 0xFF);
+       *(pDstline+6) = (mng_uint8)(iA >> 8);
+-      *(pDstline+7) = (mng_uint8)(iA && 0xFF);
++      *(pDstline+7) = (mng_uint8)(iA & 0xFF);
+     }
+ 
+@@ -15690,11 +15690,11 @@
+ 
+     *pDstline     = (mng_uint8)(iR >> 8);
+-    *(pDstline+1) = (mng_uint8)(iR && 0xFF);
++    *(pDstline+1) = (mng_uint8)(iR & 0xFF);
+     *(pDstline+2) = (mng_uint8)(iG >> 8);
+-    *(pDstline+3) = (mng_uint8)(iG && 0xFF);
++    *(pDstline+3) = (mng_uint8)(iG & 0xFF);
+     *(pDstline+4) = (mng_uint8)(iB >> 8);
+-    *(pDstline+5) = (mng_uint8)(iB && 0xFF);
++    *(pDstline+5) = (mng_uint8)(iB & 0xFF);
+     *(pDstline+6) = (mng_uint8)(iA >> 8);
+-    *(pDstline+7) = (mng_uint8)(iA && 0xFF);
++    *(pDstline+7) = (mng_uint8)(iA & 0xFF);
+ 
+     pSrcline += 4;
diff --git a/graphics/libmng/pkg-plist b/graphics/libmng/pkg-plist
index 497bfb54008a..0c113235c20b 100644
--- a/graphics/libmng/pkg-plist
+++ b/graphics/libmng/pkg-plist
@@ -1,9 +1,27 @@
 include/libmng.h
 include/libmng_conf.h
 include/libmng_types.h
+lib/cmake/libmng/MNG_TARGETS-%%CMAKE_BUILD_TYPE%%.cmake
+lib/cmake/libmng/MNG_TARGETS.cmake
+lib/libmng.a
+lib/libmng.so
+lib/libmng.so.2
+lib/libmng.so.2.0.2
+libdata/pkgconfig/libmng.pc
 man/man3/libmng.3.gz
 man/man5/jng.5.gz
 man/man5/mng.5.gz
-lib/libmng.a
-lib/libmng.so
-lib/libmng.so.1
+share/doc/mng-2.0/CHANGES
+share/doc/mng-2.0/LICENSE
+share/doc/mng-2.0/Plan1.png
+share/doc/mng-2.0/Plan2.png
+share/doc/mng-2.0/README
+share/doc/mng-2.0/README.autoconf
+share/doc/mng-2.0/README.config
+share/doc/mng-2.0/README.contrib
+share/doc/mng-2.0/README.dll
+share/doc/mng-2.0/README.examples
+share/doc/mng-2.0/README.footprint
+share/doc/mng-2.0/README.packaging
+share/doc/mng-2.0/doc.readme
+share/doc/mng-2.0/libmng.txt