Junglewise Threat Intelligence

CVE-2016-7980: SPIP CSRF in XML validator

CVE-2016-7980 · Severity: high · CVSS 8.8 · Published 2017-01-18

Technologies: Spip. Vendors: Spip.

Executive brief

A security vulnerability exists in SPIP, a popular open-source content management system. An attacker can trick an authenticated administrator into clicking a malicious link, which then performs unauthorized actions on the website using the administrator's permissions. This specific flaw allows an attacker to trigger an XML validation process that, when combined with other vulnerabilities, could lead to the complete takeover of the website and the execution of malicious code.

Technical details

A Cross-Site Request Forgery (CSRF) vulnerability exists in 'ecrire/exec/valider_xml.php' in SPIP versions 3.1.2 and earlier. The application fails to validate a unique token for requests sent to the XML validator component, allowing a remote attacker to craft a malicious URL that, if visited by a logged-in administrator, executes the 'valider_xml' action. This vulnerability is particularly dangerous as it can be chained with CVE-2016-7998 (a PHP code execution flaw in the template compiler) to achieve full remote code execution (RCE). The issue was resolved in SPIP 3.1.3 by implementing 'var_token' validation and restricting execution rights to webmasters.

Affected products

  • SPIP SPIP <= 3.1.2

Timeline

  • 2016-09-15: disclosed: Initial discovery by Sysdream Labs
  • 2016-09-28: patched: Fixes issued for CSRF issue
  • 2016-09-30: patched: SPIP 3.1.3 released
  • 2017-01-18: advisory: NVD published date

References

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