diff --git a/build/zstd/build.sh b/build/zstd/build.sh
index 13a405f663..084caee1f2 100755
--- a/build/zstd/build.sh
+++ b/build/zstd/build.sh
@@ -12,12 +12,12 @@
 # http://www.illumos.org/license/CDDL.
 # }}}
 
-# Copyright 2022 OmniOS Community Edition (OmniOSce) Association.
+# Copyright 2024 OmniOS Community Edition (OmniOSce) Association.
 
 . ../../lib/build.sh
 
 PROG=zstd
-VER=1.5.5
+VER=1.5.6
 PKG=compress/zstd
 SUMMARY="Zstandard"
 DESC="Zstandard is a real-time compression algorithm, providing high "
diff --git a/build/zstd/patches/cpudetect.patch b/build/zstd/patches/cpudetect.patch
index 58e615d258..818763543d 100644
--- a/build/zstd/patches/cpudetect.patch
+++ b/build/zstd/patches/cpudetect.patch
@@ -1,8 +1,8 @@
-diff -wpruN '--exclude=*.orig' a~/programs/util.c a/programs/util.c
+diff -wpruN --no-dereference '--exclude=*.orig' a~/programs/util.c a/programs/util.c
 --- a~/programs/util.c	1970-01-01 00:00:00
 +++ a/programs/util.c	1970-01-01 00:00:00
-@@ -1258,7 +1258,7 @@ int UTIL_countPhysicalCores(void)
-     return numPhysicalCores;
+@@ -1603,7 +1603,7 @@ int UTIL_countCores(int logical)
+     return numCores;
  }
  
 -#elif defined(__NetBSD__) || defined(__OpenBSD__) || defined(__DragonFly__) || defined(__CYGWIN__)
diff --git a/doc/packages.md b/doc/packages.md
index aa4512172d..6f9321baa2 100644
--- a/doc/packages.md
+++ b/doc/packages.md
@@ -10,7 +10,7 @@
 | compress/unzip			| 6.0			| https://sourceforge.net/projects/infozip/files/UnZip%206.x%20%28latest%29/ https://www.cvedetails.com/vulnerability-list/vendor_id-816/product_id-1395/Info-zip-Unzip.html
 | compress/xz				| 5.6.1			| https://tukaani.org/xz/
 | compress/zip				| 3.0			| https://sourceforge.net/projects/infozip/files/Zip%203.x%20%28latest%29/ http://www.info-zip.org/Zip.html
-| compress/zstd				| 1.5.5			| https://github.com/facebook/zstd/releases
+| compress/zstd				| 1.5.6			| https://github.com/facebook/zstd/releases
 | data/iso-codes			| 4.16.0		| https://salsa.debian.org/api/v4/projects/iso-codes-team%2Fiso-codes/repository/tags https://salsa.debian.org/iso-codes-team/iso-codes/tags
 | database/sqlite-3			| 3450200		| https://www.sqlite.org/download.html
 | developer/build/autoconf		| 2.72			| https://ftp.gnu.org/gnu/autoconf/