Changeset 206276 in webkit

Timestamp:

Sep 22, 2016 2:33:20 PM (8 years ago)

Author:

dbates@webkit.org

Message:

[XSS Auditor] Truncate data URLs at quotes
​https://bugs.webkit.org/show_bug.cgi?id=161937

Reviewed by David Kilzer.

Source/WebCore:

Merged from Blink:
<​https://chromium.googlesource.com/chromium/src/+/c6d6331190dd43f09459e2341c3111e796f9de12/>

Truncate a data URL at the first single or double quote character to avoid considering
characters that may come from the page content following an injected data URL.

Test: http/tests/security/xssAuditor/script-tag-with-source-data-url4.html

• html/parser/XSSAuditor.cpp:

(WebCore::truncateForSrcLikeAttribute):

LayoutTests:

• http/tests/security/xssAuditor/resources/echo-property.pl:
• http/tests/security/xssAuditor/script-tag-with-source-data-url4-expected.txt: Added.
• http/tests/security/xssAuditor/script-tag-with-source-data-url4.html: Added.

Location:

trunk

Files:

• LayoutTests/ChangeLog (modified) (1 diff)
• LayoutTests/http/tests/security/xssAuditor/resources/echo-property.pl (modified) (1 diff)
• LayoutTests/http/tests/security/xssAuditor/script-tag-with-source-data-url4-expected.txt (added)
• LayoutTests/http/tests/security/xssAuditor/script-tag-with-source-data-url4.html (added)
• Source/WebCore/ChangeLog (modified) (1 diff)
• Source/WebCore/html/parser/XSSAuditor.cpp (modified) (2 diffs)

trunk/LayoutTests/ChangeLog

@@ +1 @@
+2016-09-22  Daniel Bates  <dabates@apple.com>
+
+        [XSS Auditor] Truncate data URLs at quotes
+        https://bugs.webkit.org/show_bug.cgi?id=161937
+
+        Reviewed by David Kilzer.
+
+        * http/tests/security/xssAuditor/resources/echo-property.pl:
+        * http/tests/security/xssAuditor/script-tag-with-source-data-url4-expected.txt: Added.
+        * http/tests/security/xssAuditor/script-tag-with-source-data-url4.html: Added.
+
 2016-09-22  Ryan Haddad  <ryanhaddad@apple.com>
 

trunk/LayoutTests/http/tests/security/xssAuditor/resources/echo-property.pl

@@ -15 +15 @@
 }
 print "\">\n";
+print "<script>var y = 123;</script>";
 print "</body>\n";
 print "</html>\n";

trunk/Source/WebCore/ChangeLog

@@ +1 @@
+2016-09-22  Daniel Bates  <dabates@apple.com>
+
+        [XSS Auditor] Truncate data URLs at quotes
+        https://bugs.webkit.org/show_bug.cgi?id=161937
+
+        Reviewed by David Kilzer.
+
+        Merged from Blink: 
+        <https://chromium.googlesource.com/chromium/src/+/c6d6331190dd43f09459e2341c3111e796f9de12/>
+
+        Truncate a data URL at the first single or double quote character to avoid considering
+        characters that may come from the page content following an injected data URL.
+
+        Test: http/tests/security/xssAuditor/script-tag-with-source-data-url4.html
+
+        * html/parser/XSSAuditor.cpp:
+        (WebCore::truncateForSrcLikeAttribute):
+
 2016-09-22  Daniel Bates  <dabates@apple.com>
 

trunk/Source/WebCore/html/parser/XSSAuditor.cpp

@@ -179 +179 @@
     // In HTTP URLs, characters following the first ?, #, or third slash may come from
     // the page itself and can be merely ignored by an attacker's server when a remote
-    // script or script-like resource is requested. In DATA URLS, the payload starts at
-    // the first comma, and the the first /*, //, or <!-- may introduce a comment. Characters
-    // following this may come from the page itself and may be ignored when the script is
-    // executed. For simplicity, we don't differentiate based on URL scheme, and stop at
-    // the first # or ?, the third slash, or the first slash or < once a comma is seen.
+    // script or script-like resource is requested. In data URLs, the payload starts at
+    // the first comma, and the first /*, //, or <!-- may introduce a comment. Also
+    // data URLs may use the same string literal tricks as with script content itself.
+    // In either case, content following this may come from the page and may be ignored
+    // when the script is executed.
+    // For simplicity, we don't differentiate based on URL scheme, and stop at
+    // the first # or ?, the third slash, or the first slash, <, ', or " once a comma
+    // is seen.
     int slashCount = 0;
     bool commaSeen = false;
@@ -191 +194 @@
             || currentChar == '#'
             || ((currentChar == '/' || currentChar == '\\') && (commaSeen || ++slashCount > 2))
-            || (currentChar == '<' && commaSeen)) {
+            || (currentChar == '<' && commaSeen)
+            || (currentChar == '\'' && commaSeen)
+            || (currentChar == '"' && commaSeen)) {
             decodedSnippet.truncate(currentLength);
             return;