Firejail before 0.9.64.4 allows attackers to bypass intended access restrictions because there is a TOCTOU race condition between a stat operation and an OverlayFS mount operation.

@@ -1,6 +1,6 @@ #! /bin/sh # Guess values for system-dependent variables and create Makefiles. # Generated by GNU Autoconf 2.69 for firejail 0.9.64.2. # Generated by GNU Autoconf 2.69 for firejail 0.9.64.4. # # Report bugs to <netblue30@protonmail.com>. # @@ -580,8 +580,8 @@ MAKEFLAGS= # Identity of this package. PACKAGE\_NAME='firejail' PACKAGE\_TARNAME='firejail' PACKAGE\_VERSION='0.9.64.2' PACKAGE\_STRING='firejail 0.9.64.2' PACKAGE\_VERSION='0.9.64.4' PACKAGE\_STRING='firejail 0.9.64.4' PACKAGE\_BUGREPORT='netblue30@protonmail.com' PACKAGE\_URL='https://firejail.wordpress.com'  
@@ -711,7 +711,6 @@ enable\_option\_checking enable\_analyzer enable\_apparmor enable\_dbusproxy enable\_overlayfs enable\_usertmpfs enable\_man enable\_firetunnel @@ -1294,7 +1293,7 @@ if test "$ac\_init\_help" = "long"; then # Omit some internal or obsolete options to make the list less imposing. # This message is too long to be a string in the A/UX 3.1 sh. cat <<\_ACEOF \\\`configure' configures firejail 0.9.64.2 to adapt to many kinds of systems. \\\`configure' configures firejail 0.9.64.4 to adapt to many kinds of systems. Usage: $0 \[OPTION\]... \[VAR=VALUE\]... @@ -1356,7 +1355,7 @@ fi  
if test -n "$ac\_init\_help"; then case $ac\_init\_help in short | recursive ) echo "Configuration of firejail 0.9.64.2:";; short | recursive ) echo "Configuration of firejail 0.9.64.4:";; esac cat <<\\\_ACEOF @@ -1367,7 +1366,6 @@ Optional Features: \--enable-analyzer enable GCC 10 static analyzer \--enable-apparmor enable apparmor \--disable-dbusproxy disable dbus proxy \--disable-overlayfs disable overlayfs \--disable-usertmpfs disable tmpfs as regular user \--disable-man disable man pages \--disable-firetunnel disable firetunnel @@ -1473,7 +1471,7 @@ fi test -n "$ac\_init\_help" && exit $ac\_status if $ac\_init\_version; then cat <<\\\_ACEOF firejail configure 0.9.64.2 firejail configure 0.9.64.4 generated by GNU Autoconf 2.69 Copyright (C) 2012 Free Software Foundation, Inc. @@ -1775,7 +1773,7 @@ cat >config.log <<\_ACEOF This file contains any messages produced by compilers while running configure, to aid debugging if configure makes a mistake. It was created by firejail $as\_me 0.9.64.2, which was It was created by firejail $as\_me 0.9.64.4, which was generated by GNU Autoconf 2.69. Invocation command line was $ $0 $@ @@ -3530,18 +3528,16 @@ if test "x$enable\_dbusproxy" != "xno"; then :  
fi  
# overlayfs features temporarely disabled pending fixes HAVE\_OVERLAYFS="" # Check whether --enable-overlayfs was given. if test "${enable\_overlayfs+set}" = set; then : enableval=$enable\_overlayfs; fi  
if test "x$enable\_overlayfs" !\= "xno"; then :  
HAVE\_OVERLAYFS="\-DHAVE\_OVERLAYFS"  
  
fi # #AC\_ARG\_ENABLE(\[overlayfs\], # AS\_HELP\_STRING(\[--disable-overlayfs\], \[disable overlayfs\])) #AS\_IF(\[test "x$enable\_overlayfs" != "xno"\], \[ # HAVE\_OVERLAYFS="-DHAVE\_OVERLAYFS" # AC\_SUBST(HAVE\_OVERLAYFS) #\])  
HAVE\_USERTMPS="" # Check whether --enable-usertmpfs was given. @@ -4817,7 +4813,7 @@ cat >>$CONFIG\_STATUS <<\\\_ACEOF || ac\_write\_fail=1 \# report actual input values of CONFIG\_FILES etc. instead of their \# values after options handling. ac\_log=" This file was extended by firejail $as\_me 0.9.64.2, which was This file was extended by firejail $as\_me 0.9.64.4, which was generated by GNU Autoconf 2.69. Invocation command line was CONFIG\_FILES = $CONFIG\_FILES @@ -4871,7 +4867,7 @@ \_ACEOF cat >>$CONFIG\_STATUS <<\_ACEOF || ac\_write\_fail=1 ac\_cs\_config="\`$as\_echo "$ac\_configure\_args" | sed 's/^ //; s/\[\\\\""\\\`\\$\]/\\\\\\\\&/g'\`" ac\_cs\_version="\\\\ firejail config.status 0.9.64.2 firejail config.status 0.9.64.4 configured by $0, generated by GNU Autoconf 2.69, with options \\\\"\\$ac\_cs\_config\\\\"

CVE-2021-26910: disabled overlayfs, 0.9.64.4 testing · netblue30/firejail@97d8a03

The Elementor Contact Form DB plugin before 1.6 for WordPress allows CSRF via backend admin pages.

CVE-2021-3133: Changeset 2454670 – WordPress Plugin Repository

A Reflected Authenticated Cross-Site Scripting (XSS) vulnerability in the Newsletter plugin before 6.8.2 for WordPress allows remote attackers to trick a victim into submitting a tnpc_render AJAX request containing either JavaScript in an options parameter, or a base64-encoded JSON string containing JavaScript in the encoded_options parameter.

On July 13, 2020, our Threat Intelligence team was alerted to a recently patched vulnerability in Newsletter, a WordPress plugin with over 300,000 installations. While investigating this vulnerability, we discovered two additional, more serious vulnerabilities, including a reflected Cross-Site Scripting(XSS) vulnerability and a PHP Object Injection vulnerability.

We reached out to the plugin’s author on July 15, 2020, and received a response the next day. After fully disclosing the vulnerability on July 16, 2020, the plugin’s author released a patch the next day, on July 17, 2020.

A firewall rule to protect against the Reflected Cross-Site Scripting vulnerability was released to Wordfence Premium customers on July 15, 2020 and will become available to free Wordfence users 30 days later, on August 14, 2020.

Although the PHP Object Injection vulnerability would require additional vulnerable software to be installed, and our built-in PHP Object Injection protection would have protected against the most common exploits, we determined that a bypass was possible. Out of an abundance of caution, we created an additional firewall rule and released it to Wordfence Premium users on July 28, 2020. The PHP Object Injection firewall rule will become available to free Wordfence users on the same date as the XSS rule for this plugin, on August 14, 2020.

**Description**: Authenticated Reflected Cross-Site Scripting(XSS)  
**Affected Plugin**: Newsletter  
**Plugin Slug**: newsletter  
**Affected Versions**: < 6.8.2  
**CVE ID**: CVE-2020-35933  
**CVSS Score**: 6.5(Medium)  
**CVSS Vector**: CVSS:3.0/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:L  
**Fully Patched Version**: 6.8.2

The Newsletter plugin includes a full-featured visual editor that can be used to create visually appealing newsletters and email campaigns. It uses an AJAX function, tnpc_render_callback, to display edited blocks based on a set of options sent in the AJAX request. Unfortunately, the vulnerable versions did not filter these options, but passed them onto a second function, restore_options_from_request which used multiple methods to decode options that were passed in before displaying them using the render_block function.

    function tnpc\_render\_callback() {
        $block\_id = $\_POST\['b'\];
        $wrapper = isset($\_POST\['full'\]);
        $options = $this->restore\_options\_from\_request();

        $this->render\_block($block\_id, $wrapper, $options);
        wp\_die()

As such, it was possible for an attacker to get malicious JavaScript to display in multiple ways. The simplest method would involve sending a POST request to wp-admin/admin-ajax.php with the action parameter set to tnpc_render, the b parameter set to html, and the options parameter set to arbitrary JavaScript. Alternatively, a similar request with the options parameter set to an empty array options[]= and the encoded_options parameter set to a base64-encoded JSON string containing arbitrary JavaScript would also result in JavaScript being rendered in a logged-in user’s browser.

            if (isset($\_POST\['encoded\_options'\])) {
                $decoded\_options = $this->options\_decode($\_POST\['encoded\_options'\]);

    function options\_decode($options) {

        // Start compatibility
        if (is\_string($options) && strpos($options, 'options\[') !== false) {
            $opts = array();
            parse\_str($options, $opts);
            $options = $opts\['options'\];
        }
        // End compatibility

        if (is\_array($options)) {
            return $options;
        }

        $tmp = json\_decode($options, true);
        if (is\_null($tmp)) {
            return json\_decode(base64\_decode($options), true);
        } else {
            return $tmp;
        }
    }

We discussed Reflected XSS vulnerabilities in a previous post. Despite the fact that they require an attacker to trick a victim into performing a specific action (such as clicking a specially crafted link), they can still be used to inject backdoors or add malicious administrative users. If an attacker tricked a victim into sending a request containing a malicious JavaScript using either of these methods, the malicious JavaScript would be decoded and executed in the victim’s browser.

**Description**: PHP Object Injection  
**Affected Plugin**: Newsletter  
**Plugin Slug**: newsletter  
**Affected Versions**: < 6.8.2  
**CVE ID**: CVE-2020-35932  
**CVSS Score**: 7.5(High)  
**CVSS Vector**: CVSS:3.0/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H  
**Fully Patched Version**: 6.8.2

Although the Newsletter editor did not allow lower-level users to save changes to a given newsletter, the same tnpc_render_callback AJAX function was still accessible to all logged-in users, including subscribers. This introduced a PHP Object Injection vulnerability via the restore_options_from_request function. This function unserialized data passed in via the options[inline_edits] parameter. As such, an attacker logged-in as a subscriber could send a POST request to wp-admin/admin-ajax.php with the action parameter set to tpnc_render and the options[inline_edits] parameter set to a serialized PHP object.

        if (isset($\_POST\['options'\]) && is\_array($\_POST\['options'\])) {
            // Get all block options
            $options = stripslashes\_deep($\_POST\['options'\]);

            // Deserialize inline edits when
            // render is preformed on saving block options
            if (isset($options\['inline\_edits'\]) && is\_serialized($options\['inline\_edits'\])) {
                $options\['inline\_edits'\] = unserialize($options\['inline\_edits'\]);
            }

Although the Newsletter plugin itself did not use any code that would allow additional exploitation, this vulnerability could be used to inject a PHP object that might be processed by code from another plugin or theme and used to execute arbitrary code, upload files, or any number of other tactics that could lead to site takeover.

**How does PHP Object Injection Work?**

PHP can make use of a method called “serialization” to store complex data. In most cases serialized data consists of key => value arrays, for example:  
a:2:{s:11:"productName";s:5:"apple";s:7:"price";i:10;}  
This serialized data sample includes a productName property which is set to apple and a price property which is set to 10.

Serialized data is useful for storing settings in bulk, and many WordPress settings are stored as serialized data. Unfortunately, serialized data can also cause a security issue because it can be used to store PHP objects.

**What are PHP objects?**

Most modern PHP code is object oriented, meaning that code is organized into “classes.” These classes act like a basic template containing both variables (referred to as “properties”) and functions (referred to as “methods”). A running program can then create “objects” based on these templates, or classes. This creates not only a clear, concise structure for handling data, making code easier to maintain, it allows the same code to be reused for multiple similar tasks.

For instance, an online store could use a single class for products with properties(variables) including $price and $productName, and create a different object for each product. Each object would use the same function(method) to calculate tax, but could use a different price and product name.

If a plugin unserializes data provided by users without sanitizing that user’s input, then an attacker can send a specially crafted payload that would be unserialized into a PHP object.

On its own, an injected PHP object is not particularly dangerous. This changes, however, if the class it is based on uses so-called “magic methods”.

**What are magic methods?**

Magic methods are special functions that can be added to a class that describe what it should do when certain events happen.

For instance, the __destruct function is used in many classes to “clean up” once an object is done being used, and in many cases it does this by deleting files.

Here’s a very basic example of a vulnerable class that calculates product prices, stores a log, and deletes the log when it’s done:

class Product{

    public $price;
    public $productName;
    public $savedPriceFile;

    function \_\_construct($price, $productName){
        $this->price=$price;
        $this->productName=$productName;
        $this->savedPriceFile=$productName."pricefile.log";
    }

    function calculateTotal($quantity) {
        $total=$this->price \* $quantity;
        echo ($total);
        file\_put\_contents($this->savedPriceFile, $total);
    }

    function \_\_destruct(){
        unlink($this->savedPriceFile);
    }

}

If this code was running on a site that also had a PHP Object Injection vulnerability, an attacker could delete the wp-config.php file containing the WordPress site’s core configuration settings by sending a payload similar to the following:

O:7:"Product":3:{s:5:"price";i:2;s:11:"productName";s:6:"apples";s:14:"savedPriceFile";s:13:"wp-config.php";}

This would inject a Product object, with the $productName set to apples, the $price set to 2, and a $savedPriceFile property set to wp-config.php. Even though the object might not be used by anything else, eventually the __destruct function would run, deleting whatever $savedPriceFile was set to. In this case, the deletion of the wp-config.php file would reset the site and allow an attacker to take over by pointing the site’s new configuration to a remote database under their control.

Successfully exploiting this chain of events, also known as a “POP chain”, does require some degree of effort, since it requires:

*   Code that unserializes user input (an Object Injection vulnerability).
*   Code that uses a magic method in an insecure way.
*   Both of these need to be loaded at the same time.

Due to the fact that many plugins and themes load some, or all, of their classes on each request to the site, this is not as great of a restriction as it might appear. Additionally, although insecure usage of these “magic methods” is less common than it was in the past, such usage is not considered a vulnerability on its own since it requires the presence of a PHP Object Injection vulnerability to exploit.

Finally, although an attacker might need to know which plugins are installed in order to tailor their attack to a given POP chain, it is often fairly simple to determine this with scanning tools. The good news is that such vulnerabilities are difficult to automatically exploit in bulk, except in cases where a PHP Object Injection vulnerability and an insecure magic method are both used in the same plugin.

**Timeline**

**July 13, 2020** – Our Threat Intelligence Team begins investigating a recently patched vulnerability in the Newsletter plugin.  
**July 14, 2020** – During our investigation, we discover 2 unpatched vulnerabilities.  
**July 15, 2020** – We release a firewall rule for the reflected XSS vulnerability to Wordfence Premium users and reach out to the plugin’s author.  
**July 16, 2020** – We receive a response from the plugin’s author and provide full disclosure.  
**July 17, 2020** – Plugin author releases a patch for both vulnerabilities.  
**July 28, 2020** – We determine that an additional firewall rule is necessary to ensure full coverage for the PHP Object Injection vulnerability and release it to Wordfence Premium users.  
**August 14, 2020** – Both firewall rules become available to free Wordfence users.

**Conclusion**

In this blog post, we discussed 2 vulnerabilities in the Newsletter plugin, including a reflected XSS vulnerability and a PHP Object Injection vulnerability. We also explained what PHP Object Injection vulnerabilities are and how they can be exploited.

We strongly recommend updating to the latest version of the Newsletter plugin as soon as possible. As of this writing, that is version 6.8.3.

Wordfence Premium users have been protected against the majority of potential attacks since July 15, 2020, and have been fully protected since July 28, 2020. Sites still running the free version of Wordfence will receive firewall rules protecting against both vulnerabilities on August 14, 2020.

_Special thanks to Stefano Lissa & The Newsletter Team for their rapid response in patching these vulnerabilities._

CVE-2020-35933: Newsletter Plugin Vulnerabilities Affect Over 300,000 Sites

The site-offline plugin before 1.4.4 for WordPress lacks certain wp_create_nonce and wp_verify_nonce calls, aka CSRF.

**wp\_create\_nonce( string|int $action = \-1 )**

Creates a cryptographic token tied to a specific action, user, user session, and window of time.

**Contents**

*   Parameters
*   Return
*   More Information
*   Source
*   Related
    *   Uses
    *   Used By
*   Changelog
*   User Contributed Notes

**Parameters**

$action

(string|int) (Optional) Scalar value to add context to the nonce.

Default value: -1

Top ↑

**Return**

(string) The token.

Top ↑

**More Information**

The function should be called using the init or any subsequent action hook. Calling it outside of an action hook can lead to problems, see the ticket #14024 for details.

Top ↑

**Source**

File: wp-includes/pluggable.php

	function wp\_create\_nonce( $action = -1 ) {
		$user = wp\_get\_current\_user();
		$uid  = (int) $user->ID;
		if ( ! $uid ) {
			/\*\* This filter is documented in wp-includes/pluggable.php \*/
			$uid = apply\_filters( 'nonce\_user\_logged\_out', $uid, $action );
		}

		$token = wp\_get\_session\_token();
		$i     = wp\_nonce\_tick();

		return substr( wp\_hash( $i . '|' . $action . '|' . $uid . '|' . $token, 'nonce' ), -12, 10 );
	}

Expand full source code Collapse full source code View on Trac View on GitHub

Top ↑

**Changelog**

Changelog

Version

Description

4.0.0

Session tokens were integrated with nonce creation

2.0.3

Introduced.

Top ↑

**User Contributed Notes**

CVE-2020-35773: wp_create_nonce() | Function | WordPress Developer Resources

The ultimate-category-excluder plugin before 1.2 for WordPress allows ultimate-category-excluder.php CSRF.

Timestamp:

12/08/2020 12:29:27 PM (20 months ago)

Marios Alexandrou

Message:

Addressed minor vulnerability reported by SCA AppSec.  

Location:

ultimate-category-excluder/trunk

Files:

  

*   readme.txt (1 diff)
*   ultimate-category-excluder.php (3 diffs)

**Legend:**

Unmodified

Added

Removed

*   **ultimate-category-excluder/trunk/readme.txt**
    
    r2364782
    
    r2434070
    
     
    
    32
    
    32
    
    33
    
    33
    
    \== Changelog ==
    
     
    
    34
    
     
    
    35
    
    \= 1.2 =
    
     
    
    36
    
    \* Addressed minor vulnerability reported by SCA AppSec. If concerned, review your UCE category settings to ensure they are set as expected.
    
    34
    
    37
    
    35
    
    38
    
    \= 1.1 =
    
*   **ultimate-category-excluder/trunk/ultimate-category-excluder.php**
    
    r1490271
    
    r2434070
    
     
    
    2
    
    2
    
    /\*
    
    3
    
    3
    
    Plugin Name: Ultimate Category Excluder
    
    4
    
     
    
    Version: 1.1
    
     
    
    4
    
    Version: 1.2
    
    5
    
    5
    
    Plugin URI: http://infolific.com/technology/software-worth-using/ultimate-category-excluder/
    
    6
    
    6
    
    Description: Easily exclude categories from your front page, feeds, archives, and search results.
    
    …
    
    …
    
     
    
    42
    
    42
    
    43
    
    43
    
    function ksuce\_options\_page() {
    
    44
    
     
    
        if( isset( $\_POST\[ 'ksuce' \] ) ) { $message = ksuce\_process(); }
    
     
    
    44
    
        if( isset( $\_POST\[ 'ksuce' \] ) ) {
    
     
    
    45
    
            check\_admin\_referer( 'uce\_form' );
    
     
    
    46
    
            $message = ksuce\_process();
    
     
    
    47
    
        }
    
    45
    
    48
    
        $options = ksuce\_get\_options();
    
    46
    
    49
    
        ?>
    
    …
    
    …
    
     
    
    50
    
    53
    
            <p><?php \_e( 'Use this page to select the categories you wish to exclude and where you would like to exclude them from.', 'UCE' ); ?></p>
    
    51
    
    54
    
            <form action="options-general.php?page=ultimate-category-excluder.php" method="post">
    
     
    
    55
    
            <?php wp\_nonce\_field( 'uce\_form' ); ?>
    
    52
    
    56
    
            <table class="widefat">
    
    53
    
    57
    
            <thead>
    

**Note:** See TracChangeset for help on using the changeset viewer.

CVE-2020-35135: Changeset 2434070 – WordPress Plugin Repository

In cPanel before 90.0.17, 2FA can be bypassed via a brute-force approach (SEC-575).

CVE-2020-29136: 90 Change Log

WordPress before 5.5.2 allows stored XSS via post slugs.

CVE-2020-28038: SonarSource Blog

WordPress before 5.5.2 mishandles embeds from disabled sites on a multisite network, as demonstrated by allowing a spam embed.

WordPress 5.5.2 is now available!

This security and maintenance release features 14 bug fixes in addition to 10 security fixes. Because this is a **security release**, it is recommended that you update your sites immediately. All versions since WordPress 3.7 have also been updated.

WordPress 5.5.2 is a short-cycle security and maintenance release. The next major release will be version 5.6.

You can download WordPress 5.5.2 by downloading from WordPress.org, or visit your Dashboard → Updates and click Update Now.

If you have sites that support automatic background updates, they’ve already started the update process.

**Security Updates**

Ten security issues affect WordPress versions 5.5.1 and earlier. If you haven’t yet updated to 5.5, all WordPress versions since 3.7 have also been updated to fix the following security issues:

*   Props to Alex Concha of the WordPress Security Team for their work in hardening deserialization requests.
*   Props to David Binovec on a fix to disable spam embeds from disabled sites on a multisite network.
*   Thanks to Marc Montas from Sucuri for reporting an issue that could lead to XSS from global variables.
*   Thanks to Justin Tran who reported an issue surrounding privilege escalation in XML-RPC. He also found and disclosed an issue around privilege escalation around post commenting via XML-RPC.
*   Props to Omar Ganiev who reported a method where a DoS attack could lead to RCE.
*   Thanks to Karim El Ouerghemmi from RIPS who disclosed a method to store XSS in post slugs.
*   Thanks to Slavco for reporting, and confirmation from Karim El Ouerghemmi, a method to bypass protected meta that could lead to arbitrary file deletion.
*   Thanks to Erwan LR from WPScan who responsibly disclosed a method that could lead to CSRF.
*   And a special thanks to @zieladam who was integral in many of the releases and patches during this release.

Thank you to all of the reporters for privately disclosing the vulnerabilities. This gave the security team time to fix the vulnerabilities before WordPress sites could be attacked.

For more information, browse the full list of changes on Trac, or check out the version 5.5.2 HelpHub documentation page.

**Thanks and props!**

The 5.5.2 release was led by @whyisjake and the following release squad:  @audrasjb, @davidbaumwald, @desrosj, @johnbillion, @metalandcoffee, @noisysocks @planningwrite, @sarahricker and @sergeybiryukov.

In addition to the security researchers and release squad members mentioned above, thank you to everyone who helped make WordPress 5.5.2 happen:

Aaron Jorbin, Alex Concha, Amit Dudhat, Andrey “Rarst” Savchenko, Andy Fragen, Ayesh Karunaratne, bridgetwillard, Daniel Richards, David Baumwald, Davis Shaver, dd32, Florian TIAR, Hareesh, Hugh Lashbrooke, Ian Dunn, Igor Radovanov, Jake Spurlock, Jb Audras, John Blackbourn, Jonathan Desrosiers, Jon Brown, Joy, Juliette Reinders Folmer, kellybleck, mailnew2ster, Marcus Kazmierczak, Marius L. J., Milan Dinić, Mohammad Jangda, Mukesh Panchal, Paal Joachim Romdahl, Peter Wilson, Regan Khadgi, Robert Anderson, Sergey Biryukov, Sergey Yakimov, Syed Balkhi, szaqal21, Tellyworth, Timi Wahalahti, Timothy Jacobs, Towhidul I. Chowdhury, Vinayak Anivase, and zieladam.

CVE-2020-28033: WordPress 5.5.2 Security and Maintenance Release

WordPress before 5.5.2 mishandles deserialization requests in wp-includes/Requests/Utility/FilteredIterator.php.

CVE-2020-28032

is_protected_meta in wp-includes/meta.php in WordPress before 5.5.2 allows arbitrary file deletion because it does not properly determine whether a meta key is considered protected.

Tag

#wordpress