Menu
Emergency update for Apache Struts fixes incomplete patch for critical flaw

Emergency update for Apache Struts fixes incomplete patch for critical flaw

The previous patch did not block an attack vector that could lead to remote code execution in certain environments

The Apache Software Foundation rushed last week to update the popular Apache Struts framework after a previous security patch for a high-risk vulnerability proved to be incomplete.

The newly released Struts 2.3.16.2 strengthens the protection against a ClassLoader manipulation issue through the ParametersInterceptor feature that was thought to have been resolved in March in Struts 2.3.16.1.

The Struts developers warned users Thursday that the previous patch was insufficient and provided manual mitigation instructions until a new version of the framework for developing Java Web applications was ready.

Struts 2.3.16.2 was released later that day and extends the fix to CookieInterceptor, another functionality that according to a new advisory is vulnerable to the same type of ClassLoader manipulation attack when configured to accept all cookies.

The new advisory does not clarify if this "zero-day exploit," as Apache called it, could lead to remote code execution, but in a discussion on the Full Disclosure mailing list over the weekend, Struts developer Rene Gielen clarified that remote code execution was possible in certain environments.

"Our initial impact statement was 'classloader manipulation' which precisely names the problem," he said in an email sent to the list. "By the time we released security bulletin S2-020 [original advisory in March], we had no knowledge about how this could lead to RCE [remote code execution]."

"Strange enough, there are some smart and creative people out there," Gielen said. "Even stranger, some of them find how to exploit the said vulnerability to allow for RCE in a certain environment, a few weeks after the announcement. Luckily, the white-to-grey-hatted of these folks tend to reach a security response team then. This is what happened last week. From then on we knew we had to deal with an RCE."

Attackers have exploited remote code execution vulnerabilities in Apache Struts in the past to compromise servers that hosted applications developed with the framework. Security researchers from Trend Micro reported in August that Chinese hackers had created an automated tool for exploiting known Struts vulnerabilities.

The fact that attackers are interested in Struts increases the risk of attacks for users, so upgrading to the newly released Struts 2.3.16.2 as soon as possible is highly recommended.

There are also third-party products that include Struts and might need to be patched because of this flaw. For example, in the past, Cisco Systems updated several of its products in order to integrate a Struts patch for a critical vulnerability.


Follow Us

Join the newsletter!

Or

Sign up to gain exclusive access to email subscriptions, event invitations, competitions, giveaways, and much more.

Membership is free, and your security and privacy remain protected. View our privacy policy before signing up.

Error: Please check your email address.

Tags patch managementpatchesApache Software FoundationExploits / vulnerabilities

Featured

Slideshows

Channel gathers to celebrate the Reseller News Innovation Awards 2020 winners

Channel gathers to celebrate the Reseller News Innovation Awards 2020 winners

More than 500 channel leaders gathered in Auckland on 21 October at the ​Reseller News Innovation Awards ​2020 to celebrate the achievements of the New Zealand technology industry's top partners, start-ups, vendors, distributors and individuals.

Channel gathers to celebrate the Reseller News Innovation Awards 2020 winners
Meet the winners of the 2020 Reseller News Innovation Awards

Meet the winners of the 2020 Reseller News Innovation Awards

Reseller News honoured the standout players of the New Zealand channel in front of more than 500 technology leaders in Auckland on 21 October, recognising the achievements of top partners, start-ups, vendors, distributors and individuals.

Meet the winners of the 2020 Reseller News Innovation Awards
Meet the Reseller News 30 Under 30 Tech Awards 2020 winners

Meet the Reseller News 30 Under 30 Tech Awards 2020 winners

This year’s Reseller News 30 Under 30 Tech Awards were held as an integral part of the first entirely virtual Emerging Leaders​ forum, an annual event dedicated to identifying, educating and showcasing the New Zealand technology market’s rising stars. The 30 Under 30 Tech Awards 2020 recognised the outstanding achievements and business excellence of 30 talented individuals​, across both young leaders and those just starting out. In this slideshow, Reseller News honours this year's winners and captures their thoughts about how their ideas of leadership have changed over time.​

Meet the Reseller News 30 Under 30 Tech Awards 2020 winners
Show Comments