Struts S2-059, S2-060 Vulnerabilities (CVE-2019-0230, CVE-2019-0233) Threat Alert

Struts S2-059, S2-060 Vulnerabilities (CVE-2019-0230, CVE-2019-0233) Threat Alert

September 11, 2020 | Mina Hao

Overview

On August 13, 2020, Beijing time, Struts issued a new security bulletin to announce the fix of two vulnerabilities. S2-059 (CVE-2019-0230) is a possible remote code execution vulnerability, and S2-060 (CVE-2019-0233) is a denial-of-service vulnerability.

The two vulnerabilities were fixed in Struts 2.5.22 released in November 2019. Users are advised to upgrade as soon as possible.

Bulletin link: https://struts.apache.org/announce.html#a20200813

Vulnerability Description

  • S2-059

The vulnerability (CVE-2019-0230) results from double evaluation of values assigned to tag attributes when the Apache Struts framework is forced, which may lead to remote code execution. Only when the OGNL expression is forced in a Struts tag attribute can the vulnerability be triggered.

For more information, please visit: https://cwiki.apache.org/confluence/display/ww/s2-059

  • S2-060

The vulnerability (CVE-2019-0233) stems from the fact that an attacker may cause an access permission error via a special request when performing a file upload. As a result, the upload will fail, causing a denial-of-service attack.

For more information, please visit: https://cwiki.apache.org/confluence/display/ww/s2-059

Affected Versions

  • Struts 2.0.0 – Struts 2.5.20

Unaffected Versions

Solution

Struts has released new versions to fix the preceding vulnerabilities. Affected users are advised to upgrade as soon as possible.

Users who cannot upgrade to the latest version for the time being can refer to the workarounds provided by Struts:

  • S2-059
  • Add a proper validation of incoming parameters’ values when re-assigning them to certain Struts’ tags attributes.
  • Consider activating Proactive OGNL Expression Injection Protection.

Reference link: https://cwiki.apache.org/confluence/display/ww/s2-059

  • S2-060

Find the struts.excludedPackageNames constant in the struts-default.xml file, and add jave.io. and java.nio. to the constant’s attribute.

Reference link: https://cwiki.apache.org/confluence/display/WW/S2-060

Statement

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