diff --git a/_codeql_detected_source_root b/_codeql_detected_source_root
new file mode 120000
index 00000000..945c9b46
--- /dev/null
+++ b/_codeql_detected_source_root
@@ -0,0 +1 @@
+.
\ No newline at end of file
diff --git a/src/config/parse_config.h b/src/config/parse_config.h
index 0d7ded57..0133250f 100644
--- a/src/config/parse_config.h
+++ b/src/config/parse_config.h
@@ -1,4 +1,5 @@
 #include <ctype.h>
+#include <errno.h>
 #include <libgen.h>
 #include <stdbool.h>
 #include <stdint.h>
@@ -537,11 +538,20 @@ int32_t parse_fold_state(const char *str) {
 }
 int64_t parse_color(const char *hex_str) {
 	char *endptr;
-	int64_t hex_num = strtol(hex_str, &endptr, 16);
-	if (*endptr != '\0') {
+	errno = 0;
+	uint64_t hex_num = strtoul(hex_str, &endptr, 16);
+	
+	// Check for conversion errors
+	if (*endptr != '\0' || errno == ERANGE) {
 		return -1;
 	}
-	return hex_num;
+	
+	// Validate range for color values (0x00000000 to 0xFFFFFFFF)
+	if (hex_num > 0xFFFFFFFF) {
+		return -1;
+	}
+	
+	return (int64_t)hex_num;
 }
 
 // 辅助函数：检查字符串是否以指定的前缀开头（忽略大小写）
@@ -581,19 +591,32 @@ static char *combine_args_until_empty(char *values[], int count) {
 	// 	plus the number of commas (first_empty-1 commas)
 	total_len += (first_empty - 1);
 
-	// 	allocate memory and concatenate
+	// allocate memory and concatenate safely
 	char *combined = malloc(total_len + 1);
 	if (combined == NULL) {
 		return strdup("");
 	}
 
-	combined[0] = '\0';
+	char *ptr = combined;
+	size_t remaining = total_len + 1; // Include space for null terminator
+	
 	for (int i = 0; i < first_empty; i++) {
-		if (i > 0) {
-			strcat(combined, ",");
+		if (i > 0 && remaining > 1) {
+			*ptr++ = ',';
+			remaining--;
+		}
+		if (remaining > 1) {
+			size_t val_len = strlen(values[i]);
+			// Always leave space for null terminator
+			size_t to_copy = (val_len < remaining - 1) ? val_len : remaining - 1;
+			if (to_copy > 0) {
+				memcpy(ptr, values[i], to_copy);
+				ptr += to_copy;
+				remaining -= to_copy;
+			}
 		}
-		strcat(combined, values[i]);
 	}
+	*ptr = '\0'; // Null terminate
 
 	return combined;
 }
@@ -626,8 +649,10 @@ uint32_t parse_mod(const char *mod_str) {
 		if (strncmp(token, "code:", 5) == 0) {
 			// 处理 code: 形式
 			char *endptr;
+			errno = 0;
 			long keycode = strtol(token + 5, &endptr, 10);
-			if (endptr != token + 5 && (*endptr == '\0' || *endptr == ' ')) {
+			// Check for conversion errors: overflow or no conversion
+			if (endptr != token + 5 && (*endptr == '\0' || *endptr == ' ') && errno != ERANGE) {
 				switch (keycode) {
 				case 133:
 				case 134:
@@ -777,7 +802,16 @@ KeySymCode parse_key(const char *key_str, bool isbindsym) {
 	// 处理 code: 前缀的情况
 	if (strncmp(key_str, "code:", 5) == 0) {
 		char *endptr;
+		errno = 0;
 		xkb_keycode_t keycode = (xkb_keycode_t)strtol(key_str + 5, &endptr, 10);
+		
+		// Validate conversion
+		if (errno == ERANGE || *endptr != '\0') {
+			kc.type = KEY_TYPE_SYM;
+			kc.keysym = XKB_KEY_NoSymbol;
+			return kc;
+		}
+		
 		kc.type = KEY_TYPE_CODE;
 		kc.keycode.keycode1 = keycode; // 只设置第一个
 		kc.keycode.keycode2 = 0;
@@ -2284,7 +2318,8 @@ bool parse_option(Config *config, char *key, char *value) {
 		trim_whitespace(arg_value4);
 		trim_whitespace(arg_value5);
 
-		strcpy(binding->mode, config->keymode);
+		strncpy(binding->mode, config->keymode, sizeof(binding->mode) - 1);
+		binding->mode[sizeof(binding->mode) - 1] = '\0';
 		if (strcmp(binding->mode, "common") == 0) {
 			binding->iscommonmode = true;
 			binding->isdefaultmode = false;
@@ -3479,7 +3514,8 @@ bool parse_config(void) {
 	config.tag_rules = NULL;
 	config.tag_rules_count = 0;
 	config.cursor_theme = NULL;
-	strcpy(config.keymode, "default");
+	strncpy(config.keymode, "default", sizeof(config.keymode) - 1);
+	config.keymode[sizeof(config.keymode) - 1] = '\0';
 
 	create_config_keymap();
 
diff --git a/src/dispatch/bind_define.h b/src/dispatch/bind_define.h
index 0bfab158..c54f9a53 100644
--- a/src/dispatch/bind_define.h
+++ b/src/dispatch/bind_define.h
@@ -836,14 +836,24 @@ int32_t spawn(const Arg *arg) {
 
 		// 2. 解析参数
 		char *argv[64];
+		char *allocated_strings[64]; // Track strdup'd strings for cleanup
 		int32_t argc = 0;
+		int32_t alloc_count = 0;
+		
 		char *token = strtok((char *)arg->v, " ");
 		while (token != NULL && argc < 63) {
 			wordexp_t p;
-			if (wordexp(token, &p, 0) == 0) {
-				argv[argc++] = p.we_wordv[0];
+			if (wordexp(token, &p, 0) == 0 && p.we_wordc > 0) {
+				// Duplicate the string since we'll free the wordexp result
+				argv[argc] = strdup(p.we_wordv[0]);
+				wordfree(&p); // Free immediately after copying
+				if (argv[argc] != NULL) {
+					allocated_strings[alloc_count++] = argv[argc];
+					argc++;
+				}
 			} else {
-				argv[argc++] = token;
+				argv[argc] = token;
+				argc++;
 			}
 			token = strtok(NULL, " ");
 		}
@@ -852,7 +862,12 @@ int32_t spawn(const Arg *arg) {
 		// 3. 执行命令
 		execvp(argv[0], argv);
 
-		// 4. execvp 失败时：打印错误并直接退出（避免 coredump）
+		// 4. execvp 失败时：清理并退出
+		// If execvp succeeds, this code never runs (process replaced)
+		// If it fails, clean up allocated strings before exiting
+		for (int32_t i = 0; i < alloc_count; i++) {
+			free(allocated_strings[i]);
+		}
 		wlr_log(WLR_ERROR, "mango: execvp '%s' failed: %s\n", argv[0],
 				strerror(errno));
 		_exit(EXIT_FAILURE); // 使用 _exit 避免缓冲区刷新等操作
diff --git a/src/fetch/common.h b/src/fetch/common.h
index 58e69dc1..b04f090d 100644
--- a/src/fetch/common.h
+++ b/src/fetch/common.h
@@ -26,6 +26,9 @@ int32_t isdescprocess(pid_t p, pid_t c) {
 	return (int32_t)c;
 }
 
+// Buffer size for layout abbreviations (must match kb_layout buffer in dwl-ipc.h)
+#define LAYOUT_ABBR_SIZE 32
+
 void get_layout_abbr(char *abbr, const char *full_name) {
 	// 清空输出缓冲区
 	abbr[0] = '\0';
@@ -33,7 +36,8 @@ void get_layout_abbr(char *abbr, const char *full_name) {
 	// 1. 尝试在映射表中查找
 	for (int32_t i = 0; layout_mappings[i].full_name != NULL; i++) {
 		if (strcmp(full_name, layout_mappings[i].full_name) == 0) {
-			strcpy(abbr, layout_mappings[i].abbr);
+			strncpy(abbr, layout_mappings[i].abbr, LAYOUT_ABBR_SIZE - 1);
+			abbr[LAYOUT_ABBR_SIZE - 1] = '\0';
 			return;
 		}
 	}
@@ -73,7 +77,9 @@ void get_layout_abbr(char *abbr, const char *full_name) {
 		abbr[2] = '\0';
 	} else {
 		// 5. 最终回退：返回 "xx"
-		strcpy(abbr, "xx");
+		abbr[0] = 'x';
+		abbr[1] = 'x';
+		abbr[2] = '\0';
 	}
 }