Custom bullets with exotic chars crashes in paste from Word

[odelaere]

Are you reporting a feature request or a bug?

Bug

Provide detailed reproduction steps (if any)

1. Open a new Word document
2. define a custom bullet style (in my case the asterisk from the Symbol font)
3. use the bullet in your document
4. try to copy paste it from Word to CKEditor

Expected result

The expected result is the custom bullet to be converted into the standard one. As far as CKEditor have no way to know what the heck this char is.

Actual result

Nothing happens in the UI.

This is logged in the browser console:

14:46:42,239 SyntaxError: nothing to repeat 1 default.js:29:104
	match self-hosted:4348:16
	CKEDITOR.plugins.pastefromword.lists.removeSymbolText/< https://ckeditor.com/themes/ckeditor4/vendor/ckeditor/4.7.2/plugins/pastefromword/filter/default.js:29:105
	CKEDITOR.htmlParser.fragment.prototype.forEach https://ckeditor.com/themes/ckeditor4/vendor/ckeditor/4.7.2/ckeditor.js:282:18
	CKEDITOR.htmlParser.fragment.prototype.forEach https://ckeditor.com/themes/ckeditor4/vendor/ckeditor/4.7.2/ckeditor.js:281:496
	CKEDITOR.htmlParser.fragment.prototype.forEach https://ckeditor.com/themes/ckeditor4/vendor/ckeditor/4.7.2/ckeditor.js:281:496
	CKEDITOR.plugins.pastefromword.lists.removeSymbolText https://ckeditor.com/themes/ckeditor4/vendor/ckeditor/4.7.2/plugins/pastefromword/filter/default.js:29:79
	CKEDITOR.plugins.pastefromword.lists.convertToFakeListItem https://ckeditor.com/themes/ckeditor4/vendor/ckeditor/4.7.2/plugins/pastefromword/filter/default.js:28:194
	CKEDITOR.cleanWord/q<.elements.p https://ckeditor.com/themes/ckeditor4/vendor/ckeditor/4.7.2/plugins/pastefromword/filter/default.js:8:485
	a.prototype.exec https://ckeditor.com/themes/ckeditor4/vendor/ckeditor/4.7.2/ckeditor.js:287:163
	CKEDITOR.htmlParser.filter<.proto.onElement https://ckeditor.com/themes/ckeditor4/vendor/ckeditor/4.7.2/ckeditor.js:285:1
	CKEDITOR.htmlParser.element.prototype<.filter https://ckeditor.com/themes/ckeditor4/vendor/ckeditor/4.7.2/ckeditor.js:311:63
	CKEDITOR.htmlParser.fragment.prototype.filterChildren https://ckeditor.com/themes/ckeditor4/vendor/ckeditor/4.7.2/ckeditor.js:281:41
	CKEDITOR.cleanWord/q<.root https://ckeditor.com/themes/ckeditor4/vendor/ckeditor/4.7.2/plugins/pastefromword/filter/default.js:6:292
	a.prototype.exec https://ckeditor.com/themes/ckeditor4/vendor/ckeditor/4.7.2/ckeditor.js:287:163
	CKEDITOR.htmlParser.filter<.proto.onRoot https://ckeditor.com/themes/ckeditor4/vendor/ckeditor/4.7.2/ckeditor.js:284:345
	CKEDITOR.htmlParser.fragment.prototype.filter https://ckeditor.com/themes/ckeditor4/vendor/ckeditor/4.7.2/ckeditor.js:280:301
	CKEDITOR.htmlParser.filter<.proto.applyTo https://ckeditor.com/themes/ckeditor4/vendor/ckeditor/4.7.2/ckeditor.js:284:27
	CKEDITOR.cleanWord https://ckeditor.com/themes/ckeditor4/vendor/ckeditor/4.7.2/plugins/pastefromword/filter/default.js:17:272
	.init/</m< https://ckeditor.com/themes/ckeditor4/vendor/ckeditor/4.7.2/ckeditor.js:1107:206
	a https://ckeditor.com/themes/ckeditor4/vendor/ckeditor/4.7.2/ckeditor.js:1105:110
	.init/< https://ckeditor.com/themes/ckeditor4/vendor/ckeditor/4.7.2/ckeditor.js:1107:60
	c https://ckeditor.com/themes/ckeditor4/vendor/ckeditor/4.7.2/ckeditor.js:11:176
	CKEDITOR.event.prototype</<.fire</< https://ckeditor.com/themes/ckeditor4/vendor/ckeditor/4.7.2/ckeditor.js:13:27
	CKEDITOR.editor.prototype.fire https://ckeditor.com/themes/ckeditor4/vendor/ckeditor/4.7.2/ckeditor.js:14:195
	.init/</m< https://ckeditor.com/themes/ckeditor4/vendor/ckeditor/4.7.2/ckeditor.js:1107:82
	CKEDITOR.scriptLoader</<.load/h https://ckeditor.com/themes/ckeditor4/vendor/ckeditor/4.7.2/ckeditor.js:233:364
	CKEDITOR.scriptLoader</<.load/n https://ckeditor.com/themes/ckeditor4/vendor/ckeditor/4.7.2/ckeditor.js:234:1
	CKEDITOR.scriptLoader</<.load/q https://ckeditor.com/themes/ckeditor4/vendor/ckeditor/4.7.2/ckeditor.js:234:81
	CKEDITOR.scriptLoader</<.load/p/e.$.onload/< https://ckeditor.com/themes/ckeditor4/vendor/ckeditor/4.7.2/ckeditor.js:234:509

Other details

• Browser: Firefox 53.3.0 32 bits
• OS: Windows 7
• CKEditor version: 4.7.2 (17 Aug 2017)
• Installed CKEditor plugins: CKEditor 4.7.2 (Full) / CKEditor 4.7.3 (Full) (revision 141fd23)

[msamsel]

I can confirm problem. It seems that Paste From Word Filter wrongly interpret such character. It appears also for other characters used by regular expressions (e.g. ?, +, etc.). Example of clipboard data which cause the situation:
https://gist.github.com/msamsel/dafc4cdecc6d73c3d63fb2281464a081