CVE-2020-9484

Description from NVD

When using Apache Tomcat versions 10.0.0-M1 to 10.0.0-M4, 9.0.0.M1 to 9.0.34, 8.5.0 to 8.5.54 and 7.0.0 to 7.0.103 if a) an attacker is able to control the contents and name of a file on the server; and b) the server is configured to use the PersistenceManager with a FileStore; and c) the PersistenceManager is configured with sessionAttributeValueClassNameFilter="null" (the default unless a SecurityManager is used) or a sufficiently lax filter to allow the attacker provided object to be deserialized; and d) the attacker knows the relative file path from the storage location used by FileStore to the file the attacker has control over; then, using a specifically crafted request, the attacker will be able to trigger remote code execution via deserialization of the file under their control. Note that all of conditions a) to d) must be true for the attack to succeed.

NVD References

Description from Forti

Apache Tomcat Session Persistence Remote Code Execution

This indicates an attack attempt on a Remote Code Execution Vulnerability in Apache Tomcat.The vulnerability is due to insufficient validation of user supplied input when handling a maliciously crafted HTTP request. A successful attack may allow a remote attacker to execute arbitrary local files, via a crafted HTTP request.

Affected Products

Apache Tomcat 10.x Apache Tomcat 9.x Apache Tomcat 8.x Apache Tomcat 7.x

Impact

System Compromise: Remote attackers can gain control of vulnerable systems.

Recommended Actions

Upgrade to Apache Tomcat 10.0.0-M5 or later
Upgrade to Apache Tomcat 9.0.35 or later
Upgrade to Apache Tomcat 8.5.55 or later
Upgrade to Apache Tomcat 7.0.104 or later
Alternatively, users may configure the PersistenceManager with an appropriate value for sessionAttributeValueClassNameFilter to ensure that only application provided attributes are serialized and deserialized.

References

Refer to Information on External Sites

Software Tag: Apache(2 tweets) Tomcat(2 tweets)