Use of a Broken or Risky Cryptographic Algorithm
Impact
The function mt_rand is used to generate session tokens, this function is cryptographically flawed due to its nature being one pseudorandomness, an attacker can take advantage of the cryptographically insecure nature of this function to enumerate session tokens for accounts that are not under his/her control
Source excerpt · OSVAffected packages
Start with the recorded fix for your release branch. Check your installed version and test compatibility before upgrading. Fixing this advisory does not rule out other vulnerabilities in the release.
| Affected range | Recorded fix |
|---|---|
| Earlier releases before 3.3.4Ecosystem versions | 3.3.4 |
| From 4.0.0-alpha1 before 4.0.0Ecosystem versions | 4.0.0 |
Version evidence: OSV · GHSA-x7g2-wrrp-r6h3
View original version evidence (119 explicit versions)
Original source description
✍️ Description
The function mt_rand is used to generate session tokens, this function is cryptographically flawed due to its nature being one pseudorandomness, an attacker can take advantage of the cryptographically insecure nature of this function to enumerate session tokens for accounts that are not under his/her control
🕵️♂️ Proof of Concept
Numerous examples and attack implementations can be found in this paper . If you're looking for a practical tool that can crack your mt_rand implementation's seed value, see this project and run the following commands in a console with php5 and OpenWall's tool installed:
root$ php -r 'mt_srand(13333337); echo mt_rand( ), "\n";'
After that, copy the output (1863134308) and execute the following commands:
root$ gcc php_mt_seed.c -o php_mt_seedroot$ ./php_mt_seed 1863134308
After waiting ~1 minute you should have a few possible seeds corresponding to their PHP versions, next to your installed PHP version you should see something akin to:
seed = 0x00cb7359 = 13333337 (PHP 7.1.0+) Hey, that's your seed!
💥 Impact
An attacker could takeover accounts at random by enumerating and using access tokens.
📝 References
- https://openwall.com/php_mt_seedhttps://crypto.di.uoa.gr/CRYPTO.SEC/Randomness_Attacks_files/paper.pdf
- https://github.com/mautic/mautic/blob/5213e320b4ef4d0c51bb84c1d46a1071e8e4f7fc/app/bundles/PointBundle/Controller/TriggerController.php#L187
- https://github.com/mautic/mautic/releases/tag/3.3.4
- https://github.com/mautic/mautic/releases/tag/4.0.0
References
- Security advisory github.com/mautic/mautic/security/advisories/GHSA-x7g2-wrrp-r6h3
- Security advisory nvd.nist.gov/vuln/detail/CVE-2021-27913
- Patch github.com/mautic/mautic/commit/d1cad766a2de74e6c6b89d6d78c2a5f2e36ba91c
- Security advisory github.com/FriendsOfPHP/security-advisories/blob/master/mautic/core/CVE-2021-27913.yaml
- Source reference github.com/mautic/mautic