TYPO3-CORE-SA-2018-001: Authentication Bypass in TYPO3 CMS

Categories: Security Created by Oliver Hader
It has been discovered, that TYPO3 CMS is vulnerable to Authentication Bypass.
  • Component Type: TYPO3 CMS
  • Vulnerable subcomponent: Salted Passwords (ext:saltedpasswords)
  • Release Date: July 12, 2018
  • Vulnerability Type: Authentication Bypass
  • Affected Versions: 7.6.0 to 7.6.29, 8.0.0 to 8.7.16 and 9.0.0 to 9.3.0
  • Severity: None - Critical (depending on the default hashing algorithm)
  • Suggested CVSS v2.0: AV:N/AC:M/Au:N/C:C/I:C/A:C/E:H/RL:OF/RC:C/CDP:ND/TD:L/CR:ND/IR:ND/AR:ND
  • CVE: not assigned yet

Problem Description

It has been discovered that TYPO3’s Salted Password system extension (which is a mandatory system component) is vulnerable to Authentication Bypass when using hashing methods which are related by PHP class inheritance. In standard TYPO3 core distributions stored passwords using the blowfish hashing algorithm can be overridden when using MD5 as the default hashing algorithm by just knowing a valid username. Per default the Portable PHP hashing algorithm (PHPass) is used which is not vulnerable.

Solution

Update to TYPO3 versions 7.6.30, 8.7.17 or 9.3.1 that fix the problem described.

Credits

Thanks to TYPO3 core team member Oliver Hader  who reported and fixed the issue.

General Advice

Follow the recommendations that are given in the TYPO3 Security Guide. Please subscribe to the typo3-announce mailing list.

General Note

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