What’s Vulnerable › Vulnerabilities

CVE-2017-3203: Pivotal/Spring Spring-flex's Action Message Format (AMF3) Java implementation is vulnerable to insecure deserialization

• Severity: high (CVSS 8.1 v3.0)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 6.2% probability of exploitation in the next 30 days
• Public exploit or detection template: yes
• Published: 2018-06-11 · updated 2026-06-17
• Weakness: CWE-502

Description

The Java implementations of AMF3 deserializers in Pivotal/Spring Spring-flex derive class instances from java.io.Externalizable rather than the AMF3 specification's recommendation of flash.utils.IExternalizable. A remote attacker with the ability to spoof or control an RMI server connection may be able to send serialized Java objects that execute arbitrary code when deserialized.

Affected products

• Pivotal/Spring Spring-flex: all versions

References

• http://www.securityweek.com/flaws-java-amf-libraries-allow-remote-code-execution
• https://codewhitesec.blogspot.com/2017/04/amf.html
• https://www.kb.cert.org/vuls/id/307983
• https://www.securityfocus.com/bid/97376
• http://www.securityweek.com/flaws-java-amf-libraries-allow-remote-code-execution
• https://codewhitesec.blogspot.com/2017/04/amf.html
• https://www.kb.cert.org/vuls/id/307983
• https://www.securityfocus.com/bid/97376

Get alerted when CVE-2017-3203 or the next vulnerability affects your stack