Add changelog

trigger a notice if an incorrect modifier was used (E.g.|escape:quotes vs |escape:quote).

CHANGELOG.md

@@ -6,11 +6,17 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## [Unreleased]
 
+### Changed
+- modifier escape now triggers a E_USER_NOTICE when an unsupported escape type is used https://github.com/smarty-php/smarty/pull/649
+
+### Security
+- More advanced javascript escaping to handle https://html.spec.whatwg.org/multipage/scripting.html#restrictions-for-contents-of-script-elements thanks to m-haritonov
+
 ## [3.1.39] - 2021-02-17
 
 ### Security
-- Prevent access to `$smarty.template_object` in sandbox mode
-- Fixed code injection vulnerability by using illegal function names in `{function name='blah'}{/function}` 
+- Prevent access to `$smarty.template_object` in sandbox mode. This addresses CVE-2021-26119.
+- Fixed code injection vulnerability by using illegal function names in `{function name='blah'}{/function}`. This addresses CVE-2021-26120.
 
 ## [3.1.38] - 2021-01-08
 

SECURITY.md

@@ -0,0 +1,19 @@
+# Security Policy
+
+## Supported Versions
+
+Smarty currently supports the latest minor version of Smarty 3 and Smarty 4. (Smarty 4 has not been released yet.)
+
+| Version | Supported          |
+| ------- | ------------------ |
+| 4.0.x   | :white_check_mark: |
+| 3.1.x   | :white_check_mark: |
+| < 3.1   | :x:                |
+
+## Reporting a Vulnerability
+
+ If you have discovered a security issue with Smarty, please contact us at mail [at] simonwisselink.nl. Do not 
+ disclose your findings publicly and PLEASE PLEASE do not file an Issue.
+ 
+We will try to confirm the vulnerability and develop a fix if appropriate. When we release the fix, we will publish 
+a security release. Please let us know if you want to be credited.

libs/plugins/modifier.escape.php

@@ -184,7 +184,11 @@ function smarty_modifier_escape($string, $esc_type = 'html', $char_set = null, $
                     '"'  => '\\"',
                     "\r" => '\\r',
                     "\n" => '\\n',
-                    '</' => '<\/'
+                    '</' => '<\/',
+                    // see https://html.spec.whatwg.org/multipage/scripting.html#restrictions-for-contents-of-script-elements
+                    '<!--' => '<\!--',
+                    '<s'   => '<\s',
+                    '<S'   => '<\S'
                 )
             );
         case 'mail':
@@ -250,6 +254,7 @@ function smarty_modifier_escape($string, $esc_type = 'html', $char_set = null, $
             }
             return $return;
         default:
+            trigger_error("escape: unsupported type: $esc_type - returning unmodified string", E_USER_NOTICE);
             return $string;
     }
 }

libs/plugins/modifiercompiler.escape.php

@@ -89,9 +89,10 @@ function smarty_modifiercompiler_escape($params, Smarty_Internal_TemplateCompile
                 return 'preg_replace("%(?<!\\\\\\\\)\'%", "\\\'",' . $params[ 0 ] . ')';
             case 'javascript':
                 // escape quotes and backslashes, newlines, etc.
+                // see https://html.spec.whatwg.org/multipage/scripting.html#restrictions-for-contents-of-script-elements
                 return 'strtr(' .
                        $params[ 0 ] .
-                       ', array("\\\\" => "\\\\\\\\", "\'" => "\\\\\'", "\"" => "\\\\\"", "\\r" => "\\\\r", "\\n" => "\\\n", "</" => "<\/" ))';
+                       ', array("\\\\" => "\\\\\\\\", "\'" => "\\\\\'", "\"" => "\\\\\"", "\\r" => "\\\\r", "\\n" => "\\\n", "</" => "<\/", "<!--" => "<\!--", "<s" => "<\s", "<S" => "<\S" ))';
         }
     } catch (SmartyException $e) {
         // pass through to regular plugin fallback