diff --git a/package/odhcp6c/0001-odhcp6c-const-cast-for-c23-compatibility.patch b/package/odhcp6c/0001-odhcp6c-const-cast-for-c23-compatibility.patch
new file mode 100644
index 0000000000..cdb26a7434
--- /dev/null
+++ b/package/odhcp6c/0001-odhcp6c-const-cast-for-c23-compatibility.patch
@@ -0,0 +1,102 @@
+From 3b69378125aba61b3391bf5fe607983ce75b839c Mon Sep 17 00:00:00 2001
+From: Rosen Penev <rosenp@gmail.com>
+Date: Wed, 8 Apr 2026 14:14:56 -0700
+Subject: [PATCH] odhcp6c: const cast for c23 compatibility
+
+strpbrk is now a macro that returns const based on the parameter. Cast
+it away when we don't want const.
+
+Signed-off-by: Rosen Penev <rosenp@gmail.com>
+
+Upstream: https://github.com/openwrt/odhcp6c/pull/156
+
+Signed-off-by: Bernd Kuhls <bernd@kuhls.net>
+---
+ src/config.c | 18 +++++++++---------
+ 1 file changed, 9 insertions(+), 9 deletions(-)
+
+diff --git a/src/config.c b/src/config.c
+index 54e2d35..c1a3a99 100644
+--- a/src/config.c
++++ b/src/config.c
+@@ -338,7 +338,7 @@ static int config_parse_opt_u8(const char *src, uint8_t **dst)
+ static int config_parse_opt_string(const char *src, uint8_t **dst, const bool array)
+ {
+ 	int o_len = 0;
+-	char *sep = strpbrk(src, ARRAY_SEP);
++	char *sep = strpbrk((char*)src, ARRAY_SEP);
+ 
+ 	if (sep && !array)
+ 		return -1;
+@@ -362,7 +362,7 @@ static int config_parse_opt_string(const char *src, uint8_t **dst, const bool ar
+ 		src = sep;
+ 
+ 		if (sep)
+-			sep = strpbrk(src, ARRAY_SEP);
++			sep = strpbrk((char*)src, ARRAY_SEP);
+ 	} while (src);
+ 
+ 	return o_len;
+@@ -371,7 +371,7 @@ static int config_parse_opt_string(const char *src, uint8_t **dst, const bool ar
+ static int config_parse_opt_dns_string(const char *src, uint8_t **dst, const bool array)
+ {
+ 	int o_len = 0;
+-	char *sep = strpbrk(src, ARRAY_SEP);
++	char *sep = strpbrk((char*)src, ARRAY_SEP);
+ 
+ 	if (sep && !array)
+ 		return -1;
+@@ -399,7 +399,7 @@ static int config_parse_opt_dns_string(const char *src, uint8_t **dst, const boo
+ 		src = sep;
+ 
+ 		if (sep)
+-			sep = strpbrk(src, ARRAY_SEP);
++			sep = strpbrk((char*)src, ARRAY_SEP);
+ 	} while (src);
+ 
+ 	return o_len;
+@@ -408,7 +408,7 @@ static int config_parse_opt_dns_string(const char *src, uint8_t **dst, const boo
+ static int config_parse_opt_ip6(const char *src, uint8_t **dst, const bool array)
+ {
+ 	int o_len = 0;
+-	char *sep = strpbrk(src, ARRAY_SEP);
++	char *sep = strpbrk((char*)src, ARRAY_SEP);
+ 
+ 	if (sep && !array)
+ 		return -1;
+@@ -433,7 +433,7 @@ static int config_parse_opt_ip6(const char *src, uint8_t **dst, const bool array
+ 		src = sep;
+ 
+ 		if (sep)
+-			sep = strpbrk(src, ARRAY_SEP);
++			sep = strpbrk((char*)src, ARRAY_SEP);
+ 	} while (src);
+ 
+ 	return o_len;
+@@ -442,7 +442,7 @@ static int config_parse_opt_ip6(const char *src, uint8_t **dst, const bool array
+ static int config_parse_opt_user_class(const char *src, uint8_t **dst, const bool array)
+ {
+ 	int o_len = 0;
+-	char *sep = strpbrk(src, ARRAY_SEP);
++	char *sep = strpbrk((char*)src, ARRAY_SEP);
+ 
+ 	if (sep && !array)
+ 		return -1;
+@@ -471,7 +471,7 @@ static int config_parse_opt_user_class(const char *src, uint8_t **dst, const boo
+ 		src = sep;
+ 
+ 		if (sep)
+-			sep = strpbrk(src, ARRAY_SEP);
++			sep = strpbrk((char*)src, ARRAY_SEP);
+ 	} while (src);
+ 
+ 	return o_len;
+@@ -555,7 +555,7 @@ int config_parse_opt(const char *opt)
+ 	struct odhcp6c_opt *dopt = NULL;
+ 	int ret = -1;
+ 
+-	data = strpbrk(opt, ":");
++	data = strpbrk((char*)opt, ":");
+ 	if (!data)
+ 		return -1;
+