CVE-2020-17531 Deserialization flaw in EOL Tapestry 4.

What is CVE-2020-17531?

CVE-2020-17531 is a critical unsafe deserialization vulnerability in Apache Tapestry, published on 8 Dec 2020. An attacker can exploit it over the internet without logging in, with no action from the victim.

Official description

A Java Serialization vulnerability was found in Apache Tapestry 4. Apache Tapestry 4 will attempt to deserialize the "sp" parameter even before invoking the page's validate method, leading to deserialization without authentication. Apache Tapestry 4 reached end of life in 2008 and no update to address this issue will be released. Apache Tapestry 5 versions are not vulnerable to this issue. Users of Apache Tapestry 4 should upgrade to the latest Apache Tapestry 5 version.

Weakness: CWE-502

Which versions are affected by CVE-2020-17531?

2 open source packages ship an affected version, including org.apache.tapestry:tapestry-project. It affects 1 product.

Products include Apache Tapestry.

How do I fix CVE-2020-17531?

Upgrade org.apache.tapestry:tapestry-project to 5.0.1 or later.

Upgrade, and only deserialise data from trusted sources or with an allow-list of types. More about Unsafe deserialization.

Is CVE-2020-17531 being exploited?

There is no known exploitation of CVE-2020-17531 in the wild and no public exploit code.

Public exploit code: 1 proofs of concept on GitHub.

Other vulnerabilities in Apache Tapestry

• CVE-2022-46366 Apache Tapestry prior to version 4 (EOL) allows RCE though deserialization of untrusted input Critical 9.8
• CVE-2021-27850 Bypass of the fix for CVE-2019-0195 Critical 9.8
• CVE-2019-0195 Deserialization of Untrusted Data in Apache Tapestry Critical 9.8
• CVE-2019-10071 Timing attack on HMAC signature comparison in Apache Tapestry Critical 9.8
• CVE-2014-1972 Apache Tapestry Unsafe Object Storage High 7.8

Sources

• CVE record
• NVD
• OSV
• GitHub advisory
• How this page is made

Also known as GHSA-c566-2grg-mjwg.