CVE-2022-4141 (published 2022-11-25T14:15Z)

Heap based buffer overflow in vim/vim 9.0.0946 and below by allowing an attacker to CTRL-W gf in the expression used in the RHS of the substitute command.

CVSS v3 base score: 7.8, HIGH (CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H)

Weakness information:
cwe_id: CWE-122
cwe_name: Heap-based Buffer Overflow
description: A heap overflow condition is a buffer overflow, where the buffer that can be overwritten is allocated in the heap portion of memory, generally meaning that the buffer was allocated using a routine such as malloc().
extended_description: 
            
            
         
         

Fix information:
repo_url: https://github.com/vim/vim
commit_details: repo_url: https://github.com/vim/vim
author: Bram Moolenaar
author_date: 2022-11-25 13:03:31+00:00
msg: patch 9.0.0947: invalid memory access in substitute with function

Problem:    Invalid memory access in substitute with function that goes to
            another file.
Solution:   Check for text locked in CTRL-W gf.
repository: repo_url: https://github.com/vim/vim
repo_name: vim/vim
description: The official Vim repository
repo_language: Vim Script
owner: vim
file_changes: filename: normal.c
change_type: ModificationType.MODIFY
diff: @@ -188,13 +188,33 @@ check_text_locked(oparg_T *oap)
 {
     if (text_locked())
     {
-	clearopbeep(oap);
+	if (oap != NULL)
+	    clearopbeep(oap);
 	text_locked_msg();
 	return TRUE;
     }
     return FALSE;
 }
 
+/*
+ * If text is locked, "curbuf_lock" or "allbuf_lock" is set:
+ * Give an error message, possibly beep and return TRUE.
+ * "oap" may be NULL.
+ */
+    int
+check_text_or_curbuf_locked(oparg_T *oap)
+{
+    if (check_text_locked(oap))
+	return TRUE;
+    if (curbuf_locked())
+    {
+	if (oap != NULL)
+	    clearop(oap);
+	return TRUE;
+    }
+    return FALSE;
+}
+
 /*
  * Handle the count before a normal command and set cap->count0.
  */
@@ -798,8 +818,7 @@ normal_cmd(
 	goto normal_end;
     }
 
-    if ((nv_cmds[idx].cmd_flags & NV_NCW)
-				&& (check_text_locked(oap) || curbuf_locked()))
+    if ((nv_cmds[idx].cmd_flags & NV_NCW) && check_text_or_curbuf_locked(oap))
 	// this command is not allowed now
 	goto normal_end;
 
@@ -4026,13 +4045,9 @@ nv_gotofile(cmdarg_T *cap)
     char_u	*ptr;
     linenr_T	lnum = -1;
 
-    if (check_text_locked(cap->oap))
-	return;
-    if (curbuf_locked())
-    {
-	clearop(cap->oap);
+    if (check_text_or_curbuf_locked(cap->oap))
 	return;
-    }
+
 #ifdef FEAT_PROP_POPUP
     if (ERROR_IF_TERM_POPUP_WINDOW)
 	return;

programming_language: C
filename: normal.pro
change_type: ModificationType.MODIFY
diff: @@ -1,4 +1,5 @@
 /* normal.c */
+int check_text_or_curbuf_locked(oparg_T *oap);
 void normal_cmd(oparg_T *oap, int toplevel);
 void check_visual_highlight(void);
 void end_visual_mode(void);

programming_language: C
filename: test_substitute.vim
change_type: ModificationType.MODIFY
diff: @@ -1096,6 +1096,25 @@ func Test_sub_edit_scriptfile()
   bwipe!
 endfunc
 
+" This was editing another file from the expression.
+func Test_sub_expr_goto_other_file()
+  call writefile([''], 'Xfileone', 'D')
+  enew!
+  call setline(1, ['a', 'b', 'c', 'd',
+	\ 'Xfileone zzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzz'])
+
+  func g:SplitGotoFile()
+    exe "sil! norm 0\<C-W>gf"
+    return ''
+  endfunc
+
+  $
+  s/\%')/\=g:SplitGotoFile()
+
+  delfunc g:SplitGotoFile
+  bwipe!
+endfunc
+
 " Test for the 2-letter and 3-letter :substitute commands
 func Test_substitute_short_cmd()
   new

programming_language: Lua
filename: version.c
change_type: ModificationType.MODIFY
diff: @@ -695,6 +695,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    947,
 /**/
     946,
 /**/

programming_language: Ruby
filename: window.c
change_type: ModificationType.MODIFY
diff: @@ -567,6 +567,8 @@ newwindow:
     case Ctrl_F:
 wingotofile:
 		CHECK_CMDWIN;
+		if (check_text_or_curbuf_locked(NULL))
+		    break;
 
 		ptr = grab_file_name(Prenum1, &lnum);
 		if (ptr != NULL)
@@ -885,7 +887,7 @@ win_split(int size, int flags)
  * When "new_wp" is NULL: split the current window in two.
  * When "new_wp" is not NULL: insert this window at the far
  * top/left/right/bottom.
- * return FAIL for failure, OK otherwise
+ * Return FAIL for failure, OK otherwise.
  */
     int
 win_split_ins(

programming_language: C