Version 4.9.3

Fix: c.lang.security.insecure-use-strcat-fn.insecure-use-strcat-fn security vulnerability

Found by OrbisAI Security

.github/workflows/ci.yml

@@ -131,7 +131,7 @@ jobs:
         sudo apt-get update -qq
         sudo apt-get --yes --no-install-recommends install ${{ env.CHECK_DEPS_UBUNTU }}
         pipx install msgcheck ruff
-        cargo install --version 0.0.10 poexam
+        cargo install --version 0.0.12 poexam
 
     - name: Check gettext files (msgcheck)
       run: msgcheck po/*.po

.poexam/poexam.toml

@@ -7,9 +7,11 @@ select = [
     "checks",
 ]
 ignore = [
+    "acronyms",
     "brackets",
     "double-quotes",
     "double-words",
+    "functions",
     "header",
     "html-tags",
     "paths",

CHANGELOG.md

@@ -6,6 +6,18 @@ SPDX-License-Identifier: GPL-3.0-or-later
 
 # WeeChat ChangeLog
 
+## Version 4.9.3 (2026-07-05)
+
+### Fixed
+
+- core: fix buffer overflow in connection to SOCKS5 proxy ([#2325](https://github.com/weechat/weechat/issues/2325))
+- core: fix possible buffer overflow in command /color alias ([#2330](https://github.com/weechat/weechat/issues/2330))
+- core: fix possible buffer overflow in list of commands displayed by /help ([#2330](https://github.com/weechat/weechat/issues/2330))
+- api: do not free dynamic string on error in function string_dyn_concat
+- relay/api: fix memory leak in resources "handshake", "input" and "completion" ([GHSA-wmpc-m6g9-fwj8](https://github.com/weechat/weechat/security/advisories/GHSA-wmpc-m6g9-fwj8))
+- relay: fix read of uncompressed websocket frame ([#2331](https://github.com/weechat/weechat/issues/2331))
+- xfer: fix out-of-bounds write in xfer file transfer resume ([#2326](https://github.com/weechat/weechat/issues/2326))
+
 ## Version 4.9.2 (2026-06-07)
 
 ### Fixed
@@ -25,9 +37,9 @@ SPDX-License-Identifier: GPL-3.0-or-later
 
 - core: fix option weechat.look.color_real_white not applied when color is "white" on 16+ colors terminals ([#1742](https://github.com/weechat/weechat/issues/1742))
 - irc: fix tag in message with list of names when joining a channel
-- relay: limit size of decompressed websocket frame with permessage-deflate to prevent memory exhaustion ([GHSA-v2v4-45wm-5cr3](https://github.com/weechat/weechat/security/advisories/GHSA-v2v4-45wm-5cr3))
+- relay: limit size of decompressed websocket frame with permessage-deflate to prevent memory exhaustion ([GHSA-v2v4-45wm-5cr3](https://github.com/weechat/weechat/security/advisories/GHSA-v2v4-45wm-5cr3), [CVE-2026-53524](https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2026-53524))
-- relay: fix timing attack on password authentication ([GHSA-vhv8-g2r9-cwcc](https://github.com/weechat/weechat/security/advisories/GHSA-vhv8-g2r9-cwcc))
+- relay: fix timing attack on password authentication ([GHSA-vhv8-g2r9-cwcc](https://github.com/weechat/weechat/security/advisories/GHSA-vhv8-g2r9-cwcc), [CVE-2026-53525](https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2026-53525))
-- api, relay: fix timing attack on TOTP validation ([GHSA-vhv8-g2r9-cwcc](https://github.com/weechat/weechat/security/advisories/GHSA-vhv8-g2r9-cwcc))
+- api, relay: fix timing attack on TOTP validation ([GHSA-vhv8-g2r9-cwcc](https://github.com/weechat/weechat/security/advisories/GHSA-vhv8-g2r9-cwcc), [CVE-2026-53525](https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2026-53525))
 
 ## Version 4.9.0 (2026-03-29)
 

doc/en/weechat_plugin_api.en.adoc

@@ -3474,6 +3474,8 @@ Concatenate a string to a dynamic string.
 The pointer _*string_ can change if the string is reallocated (if there is
 not enough space to concatenate the string).
 
+In case of error, the dynamic string is left unchanged.
+
 Prototype:
 
 [source,c]

doc/en/weechat_relay_api.en.adoc

@@ -1028,6 +1028,13 @@ Path parameters:
   confused with the buffer number, which is different)
 * `buffer_name` (string, **required**): buffer name
 
+Query parameters:
+
+* `colors` (string, optional, default: `ansi`): how to return strings with color codes:
+** `ansi`: return ANSI color codes
+** `weechat`: return WeeChat internal color codes
+** `strip`: strip colors
+
 Request example: get nicks of a buffer:
 
 [source,shell]

doc/fr/weechat_plugin_api.fr.adoc

@@ -3532,6 +3532,8 @@ Concaténer une chaîne dans une chaîne dynamique.
 Le pointeur _*string_ peut changer si la chaîne est réallouée (s'il n'y a pas
 assez de place pour concaténer la chaîne).
 
+En cas d'erreur, la chaîne dynamique reste inchangée.
+
 Prototype :
 
 [source,c]

doc/fr/weechat_relay_api.fr.adoc

@@ -1040,6 +1040,14 @@ Paramètres de chemin :
   confondre avec le numéro du tampon, qui est différent)
 * `buffer_name` (chaîne, **obligatoire**) : nom du tampon
 
+Paramètres de requête :
+
+* `colors` (chaîne, facultatif, par défaut : `ansi`) : comment les chaînes avec
+  des couleurs sont retournées :
+** `ansi` : retourner les codes couleur ANSI
+** `weechat` : retourner les codes couleur internes WeeChat
+** `strip` : supprimer les couleurs
+
 Exemple de requête : obtenir les pseudos d'un tampon :
 
 [source,shell]

doc/it/weechat_plugin_api.it.adoc

@@ -3635,6 +3635,9 @@ Concatenate a string to a dynamic string.
 The pointer _*string_ can change if the string is reallocated (if there is
 not enough space to concatenate the string).
 
+// TRANSLATION MISSING
+In case of error, the dynamic string is left unchanged.
+
 Prototipo:
 
 [source,c]

doc/ja/weechat_plugin_api.ja.adoc

@@ -3586,6 +3586,9 @@ _WeeChat バージョン 1.8 以上で利用可, updated in 3.0_
 文字列が再確保された場合 (文字列を連結するのに十分なサイズが確保されていなかった場合)
 にはポインタ _*string_ が変わる可能性があります。
 
+// TRANSLATION MISSING
+In case of error, the dynamic string is left unchanged.
+
 プロトタイプ:
 
 [source,c]

doc/sr/weechat_plugin_api.sr.adoc

@@ -3356,6 +3356,9 @@ _WeeChat ≥ 1.8, ажурирано у верзији 3.0._
 
 Показивач на стринг _*string_ може да се промени ако се стринг реалоцира (у случају да нема довољно простора за надовезивање стринга).
 
+// TRANSLATION MISSING
+In case of error, the dynamic string is left unchanged.
+
 Прототип:
 
 [source,c]

doc/sr/weechat_relay_api.sr.adoc

@@ -1024,12 +1024,19 @@ GET /api/buffers/{id_бафера}/nicks
 GET /api/buffers/{име_бафера}/nicks
 ----
 
-Параметри упита:
+Параметри путање:
 
 * `id_бафера` (цео број, **обавезно**): јединствени идентификатор бафера (не треба
   да се помеша са бројем бафера, то је нешто друго)
 * `име_бафера` (стринг, **обавезно**): име бафера
 
+Параметри упита:
+
+* `colors` (стринг, није обавезно, подразумевано: `ansi`): како се враћају стрингови са кодовима боје:
+** `ansi`: враћају се ANSI кодови боје
+** `weechat`: враћају се WeeChat интерни кодови боје
+** `strip`: уклањају се боје
+
 Пример захтева: врати надимке бафера:
 
 [source,shell]

po/de.po

@@ -29,7 +29,7 @@ msgstr ""
 "Project-Id-Version: WeeChat\n"
 "Report-Msgid-Bugs-To: flashcode@flashtux.org\n"
 "POT-Creation-Date: 2026-03-21 17:24+0100\n"
-"PO-Revision-Date: 2026-03-21 17:24+0100\n"
+"PO-Revision-Date: 2026-07-03 08:28+0200\n"
 "Last-Translator: Nils Görs <weechatter@arcor.de>\n"
 "Language-Team: German <kde-i18n-de@kde.org>\n"
 "Language: de_DE\n"
@@ -17330,7 +17330,7 @@ msgstr ""
 "Um Tastenkurzbefehle im Skript-Buffer direkt nutzen zu können (zum Beispiel: "
 "alt+i = installieren, alt+r = entfernen, ...), muss diese Einstellung "
 "aktiviert werden. Andernfalls können Aktionen nur über die Eingabezeile "
-"durchgeführt werden: i,r..."
+"durchgeführt werden: i,r, ..."
 
 msgid "color for status \"autoloaded\" (\"a\")"
 msgstr "Farbe in der der Status \"autoloaded\" (\"a\") dargestellt werden soll"

src/core/core-command.c

@@ -1720,17 +1720,12 @@ COMMAND_CALLBACK(color)
             else
                 str_alias = argv[i];
         }
-        str_color[0] = '\0';
+        snprintf (str_color, sizeof (str_color),
-        if (str_alias)
+                  "%s%s%s%s",
-        {
+                  (str_alias) ? ";" : "",
-            strcat (str_color, ";");
+                  (str_alias) ? str_alias : "",
-            strcat (str_color, str_alias);
+                  (str_rgb) ? ";" : "",
-        }
+                  (str_rgb) ? str_rgb : "");
-        if (str_rgb)
-        {
-            strcat (str_color, ";");
-            strcat (str_color, str_rgb);
-        }
 
         /* add color alias */
         snprintf (str_command, sizeof (str_command),
@@ -2980,7 +2975,7 @@ command_help_list_plugin_commands (struct t_weechat_plugin *plugin,
     struct t_gui_buffer *ptr_buffer;
     int command_found, length, max_length, list_size;
     int cols, lines, col, line, index;
-    char str_format[64], str_command[256], str_line[2048];
+    char str_format[64], str_command[256], **str_line;
 
     if (verbose)
     {
@@ -3083,27 +3078,29 @@ command_help_list_plugin_commands (struct t_weechat_plugin *plugin,
             }
 
             /* display lines with commands, in columns */
-            for (line = 0; line < lines; line++)
+            str_line = string_dyn_alloc (256);
+            if (str_line)
             {
-                str_line[0] = '\0';
+                for (line = 0; line < lines; line++)
-                for (col = 0; col < cols; col++)
                 {
-                    index = (col * lines) + line;
+                    string_dyn_copy (str_line, NULL);
-                    if (index < list_size)
+                    for (col = 0; col < cols; col++)
                     {
-                        item = weelist_get (list, index);
+                        index = (col * lines) + line;
-                        if (item)
+                        if (index < list_size)
                         {
-                            if (strlen (str_line) + strlen (weelist_string (item)) + 1 < (int)sizeof (str_line))
+                            item = weelist_get (list, index);
+                            if (item)
                             {
                                 snprintf (str_command, sizeof (str_command),
                                           str_format, weelist_string (item));
-                                strcat (str_line, str_command);
+                                string_dyn_concat (str_line, str_command, -1);
                             }
                         }
                     }
+                    gui_chat_printf (NULL, "%s", *str_line);
                 }
-                gui_chat_printf (NULL, "%s", str_line);
+                string_dyn_free (str_line, 1);
             }
         }
 

src/core/core-network.c

@@ -581,7 +581,13 @@ network_pass_socks5proxy (struct t_proxy *proxy, int sock, const char *address,
                           int port)
 {
     struct t_network_socks5 socks5;
-    unsigned char buffer[288];
+    /*
+     * buffer must be large enough for the username/password authentication
+     * request, which is the longest message sent/received here; according to
+     * RFC 1929 it is: version (1) + username length (1) + username (max 255)
+     * + password length (1) + password (max 255)
+     */
+    unsigned char buffer[2 + 255 + 1 + 255];
     int username_len, password_len, addr_len, addr_buffer_len;
     unsigned char *addr_buffer;
     char *username, *password;
@@ -630,6 +636,18 @@ network_pass_socks5proxy (struct t_proxy *proxy, int sock, const char *address,
         username_len = strlen (username);
         password_len = strlen (password);
 
+        /*
+         * username and password length are each stored on a single byte
+         * (RFC 1929), so they cannot exceed 255 bytes: reject longer values,
+         * otherwise the memcpy calls below would overflow the buffer
+         */
+        if ((username_len > 255) || (password_len > 255))
+        {
+            free (username);
+            free (password);
+            return 0;
+        }
+
         /* make username/password buffer */
         buffer[0] = 1;
         buffer[1] = (unsigned char) username_len;

src/core/core-string.c

@@ -4768,6 +4768,8 @@ string_dyn_copy (char **string, const char *new_string)
  * if the string had to be extended, or the same pointer if there was enough
  * size to concatenate the new string.
  *
+ * In case of error, the dynamic string is left unchanged.
+ *
  * Return:
  *   1: OK
  *   0: error
@@ -4803,11 +4805,7 @@ string_dyn_concat (char **string, const char *add, int bytes)
             new_size_alloc = new_size;
         string_realloc = realloc (ptr_string_dyn->string, new_size_alloc);
         if (!string_realloc)
-        {
-            free (ptr_string_dyn->string);
-            free (ptr_string_dyn);
             return 0;
-        }
         ptr_string_dyn->string = string_realloc;
         ptr_string_dyn->size_alloc = new_size_alloc;
     }

src/core/core-url.c

@@ -143,8 +143,10 @@ struct t_url_constant url_auth[] =
 
 struct t_url_constant url_authtype[] =
 {
+#if LIBCURL_VERSION_NUM < 0x081600 /* < 8.22.0 */
     URL_DEF_CONST(_TLSAUTH, NONE),
     URL_DEF_CONST(_TLSAUTH, SRP),
+#endif
     { NULL, 0 },
 };
 
@@ -409,9 +411,11 @@ struct t_url_option url_options[] =
     URL_DEF_OPTION(PASSWORD, STRING, NULL),
     URL_DEF_OPTION(PROXYUSERNAME, STRING, NULL),
     URL_DEF_OPTION(PROXYPASSWORD, STRING, NULL),
+#if LIBCURL_VERSION_NUM < 0x081600 /* < 8.22.0 */
     URL_DEF_OPTION(TLSAUTH_TYPE, MASK, url_authtype),
     URL_DEF_OPTION(TLSAUTH_USERNAME, STRING, NULL),
     URL_DEF_OPTION(TLSAUTH_PASSWORD, STRING, NULL),
+#endif
     URL_DEF_OPTION(SASL_AUTHZID, STRING, NULL),
 
     URL_DEF_OPTION(SASL_IR, LONG, NULL),
@@ -626,9 +630,11 @@ struct t_url_option url_options[] =
     URL_DEF_OPTION(PROXY_SSL_OPTIONS, LONG, url_ssl_options),
     URL_DEF_OPTION(PROXY_SSL_VERIFYHOST, LONG, NULL),
     URL_DEF_OPTION(PROXY_SSL_VERIFYPEER, LONG, NULL),
+#if LIBCURL_VERSION_NUM < 0x081600 /* < 8.22.0 */
     URL_DEF_OPTION(PROXY_TLSAUTH_PASSWORD, STRING, NULL),
     URL_DEF_OPTION(PROXY_TLSAUTH_TYPE, STRING, NULL),
     URL_DEF_OPTION(PROXY_TLSAUTH_USERNAME, STRING, NULL),
+#endif
     URL_DEF_OPTION(TLS13_CIPHERS, LIST, NULL),
     URL_DEF_OPTION(PROXY_TLS13_CIPHERS, LIST, NULL),
 #if LIBCURL_VERSION_NUM >= 0x074700 /* 7.71.0 */

src/gui/curses/headless/main.c

@@ -47,7 +47,7 @@ void
 daemonize (void)
 {
     pid_t pid;
-    int fd, i;
+    int fd, i, rc;
 
     printf ("%s ", _("Running WeeChat in background..."));
 
@@ -77,8 +77,9 @@ daemonize (void)
         close (i);
     }
     fd = open ("/dev/null", O_RDWR);
-    (void) dup (fd);
+    rc = dup (fd);
-    (void) dup (fd);
+    rc = dup (fd);
+    (void) rc;
 }
 
 /*

src/gui/gui-buffer.c

@@ -3804,6 +3804,7 @@ gui_buffer_close (struct t_gui_buffer *buffer)
 
     gui_hotlist_remove_buffer (buffer, 1);
     free (buffer->hotlist_removed);
+    buffer->hotlist_removed = NULL;
     if (gui_hotlist_initial_buffer == buffer)
         gui_hotlist_initial_buffer = NULL;
 
@@ -3822,55 +3823,85 @@ gui_buffer_close (struct t_gui_buffer *buffer)
     /* free all lines */
     gui_line_free_all (buffer);
     free (buffer->own_lines);
+    buffer->own_lines = NULL;
     free (buffer->mixed_lines);
+    buffer->mixed_lines = NULL;
 
     /* free some data */
     gui_buffer_undo_free_all (buffer);
     gui_history_buffer_free (buffer);
     gui_completion_free (buffer->completion);
+    buffer->completion = NULL;
     gui_nicklist_remove_all (buffer);
     gui_nicklist_remove_group (buffer, buffer->nicklist_root);
+    buffer->nicklist_root = NULL;
     hashtable_free (buffer->hotlist_max_level_nicks);
+    buffer->hotlist_max_level_nicks = NULL;
     gui_key_free_all (-1, &buffer->keys, &buffer->last_key,
                       &buffer->keys_count, 0);
     gui_buffer_local_var_remove_all (buffer);
     hashtable_free (buffer->local_variables);
+    buffer->local_variables = NULL;
     free (buffer->plugin_name_for_upgrade);
+    buffer->plugin_name_for_upgrade = NULL;
     free (buffer->name);
+    buffer->name = NULL;
     free (buffer->full_name);
+    buffer->full_name = NULL;
     free (buffer->old_full_name);
+    buffer->old_full_name = NULL;
     free (buffer->short_name);
+    buffer->short_name = NULL;
     free (buffer->title);
+    buffer->title = NULL;
     free (buffer->modes);
+    buffer->modes = NULL;
     free (buffer->input_prompt);
+    buffer->input_prompt = NULL;
     free (buffer->input_buffer);
+    buffer->input_buffer = NULL;
     free (buffer->input_undo_snap);
+    buffer->input_undo_snap = NULL;
     free (buffer->text_search_input);
+    buffer->text_search_input = NULL;
     if (buffer->text_search_regex_compiled)
     {
         regfree (buffer->text_search_regex_compiled);
         free (buffer->text_search_regex_compiled);
+        buffer->text_search_regex_compiled = NULL;
     }
     free (buffer->highlight_words);
+    buffer->highlight_words = NULL;
     free (buffer->highlight_disable_regex);
+    buffer->highlight_disable_regex = NULL;
     if (buffer->highlight_disable_regex_compiled)
     {
         regfree (buffer->highlight_disable_regex_compiled);
         free (buffer->highlight_disable_regex_compiled);
+        buffer->highlight_disable_regex_compiled = NULL;
     }
     free (buffer->highlight_regex);
+    buffer->highlight_regex = NULL;
     if (buffer->highlight_regex_compiled)
     {
         regfree (buffer->highlight_regex_compiled);
         free (buffer->highlight_regex_compiled);
+        buffer->highlight_regex_compiled = NULL;
     }
     free (buffer->highlight_tags_restrict);
+    buffer->highlight_tags_restrict = NULL;
     string_free_split_tags (buffer->highlight_tags_restrict_array);
+    buffer->highlight_tags_restrict_array = NULL;
     free (buffer->highlight_tags);
+    buffer->highlight_tags = NULL;
     string_free_split_tags (buffer->highlight_tags_array);
+    buffer->highlight_tags_array = NULL;
     free (buffer->input_callback_data);
+    buffer->input_callback_data = NULL;
     free (buffer->close_callback_data);
+    buffer->close_callback_data = NULL;
     free (buffer->nickcmp_callback_data);
+    buffer->nickcmp_callback_data = NULL;
 
     /* remove buffer from buffers list */
     if (buffer->prev_buffer)

src/plugins/relay/api/relay-api-protocol.c

@@ -402,7 +402,10 @@ RELAY_API_PROTOCOL_CALLBACK(handshake)
     if (json_body)
     {
         if (!cJSON_IsObject (json_body))
+        {
+            cJSON_Delete (json_body);
             return RELAY_API_PROTOCOL_RC_BAD_REQUEST;
+        }
         json_algos = cJSON_GetObjectItem (json_body, "password_hash_algo");
         if (json_algos)
         {
@@ -781,8 +784,13 @@ RELAY_API_PROTOCOL_CALLBACK(input)
     char str_delay[32];
 
     json_body = cJSON_Parse (client->http_req->body);
-    if (!json_body || !cJSON_IsObject (json_body))
+    if (!json_body)
         return RELAY_API_PROTOCOL_RC_BAD_REQUEST;
+    if (!cJSON_IsObject (json_body))
+    {
+        cJSON_Delete (json_body);
+        return RELAY_API_PROTOCOL_RC_BAD_REQUEST;
+    }
 
     /* get buffer either by name or by id */
     ptr_buffer = NULL;
@@ -908,8 +916,13 @@ RELAY_API_PROTOCOL_CALLBACK(completion)
     struct t_gui_buffer *ptr_buffer;
 
     json_body = cJSON_Parse (client->http_req->body);
-    if (!json_body || !cJSON_IsObject(json_body))
+    if (!json_body)
         return RELAY_API_PROTOCOL_RC_BAD_REQUEST;
+    if (!cJSON_IsObject(json_body))
+    {
+        cJSON_Delete (json_body);
+        return RELAY_API_PROTOCOL_RC_BAD_REQUEST;
+    }
 
     /* get buffer either by name or by id */
     ptr_buffer = NULL;

src/plugins/relay/relay-websocket.c

@@ -653,7 +653,7 @@ relay_websocket_decode_frame (const unsigned char *buffer,
     size_t size_decompressed;
     char *payload_decompressed;
     struct t_relay_websocket_frame *frames2, *ptr_frame;
-    int size, masked_frame, mask[4];
+    int size, compressed, masked_frame, mask[4];
 
     if (!buffer || !frames || !num_frames)
         return 0;
@@ -674,6 +674,9 @@ relay_websocket_decode_frame (const unsigned char *buffer,
 
         opcode = buffer[index_buffer] & 15;
 
+        /* RSV1 indicates whether this message is compressed */
+        compressed = (buffer[index_buffer] & 64) ? 1 : 0;
+
         /* check if frame is masked */
         masked_frame = (buffer[index_buffer + 1] & 128) ? 1 : 0;
 
@@ -780,9 +783,9 @@ relay_websocket_decode_frame (const unsigned char *buffer,
 
         /*
          * decompress data if frame is not empty and if "permessage-deflate"
-         * is enabled
+         * is enabled and the message is compressed
          */
-        if ((length_frame > 0) && ws_deflate && ws_deflate->enabled)
+        if ((length_frame > 0) && ws_deflate && ws_deflate->enabled && compressed)
         {
             if (!ws_deflate->strm_inflate)
             {

src/plugins/xfer/xfer-dcc.c

@@ -242,8 +242,8 @@ int
 xfer_dcc_resume_hash (struct t_xfer *xfer)
 {
     char *buf;
-    unsigned long long total_read;
+    unsigned long long total_read, length_buf, to_read;
-    ssize_t length_buf, to_read, num_read;
+    ssize_t num_read;
     int ret, fd;
 
     total_read = 0;

version.sh

@@ -41,8 +41,8 @@
 #     devel-number   the devel version as hex number ("0x04010000" for "4.1.0-dev")
 #
 
-weechat_stable="4.9.2"
+weechat_stable="4.9.3"
-weechat_devel="4.9.2"
+weechat_devel="4.9.3"
 
 stable_major=$(echo "${weechat_stable}" | cut -d"." -f1)
 stable_minor=$(echo "${weechat_stable}" | cut -d"." -f2)