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

Exp

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.

Published: 2018-06-11 Last update: 2024-11-21 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2017-3203 is rated High Exploit Risk (79.7/100): CVSS High severity, with high exploitation likelihood (EPSS 13.42%, 94th percentile). 1 public exploit reference(s) are indexed (Exploit-DB). Public exploits are available—assess exposure, apply mitigations, and prioritize patching.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Public exploit references (Exploit-DB) for CVE-2017-3203

EDB-ID Source Kind Published Link
— nvd_ref exploit_tag Exploit-DB ↗

Exploit prediction scoring system (EPSS) score for CVE-2017-3203

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2025-12-26 14.02% 13.42% -0.60%
2 2025-05-12 14.47% 14.02% -0.45%
3 2025-03-30 — 14.47% —

Full EPSS history (13 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2017-3203

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
8.1 3.0 HIGH
CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:H)
Even with access, the exploit needs extra luck, timing, or a fussy environment to actually work.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 2.2 5.9 [email protected]
6.8 2.0 MEDIUM
AV:N/AC:M/Au:N/C:P/I:P/A:P Click to expand
Access vector (AV:N)
Can be exploited remotely over network reachability.
Access complexity (AC:M)
Exploitation needs some favorable conditions, but not exceptional ones.
Authentication (AU:N)
No authentication is required.
Confidentiality impact (C:P)
Partial confidentiality impact.
Integrity impact (I:P)
Partial integrity impact.
Availability impact (A:P)
Partial availability impact.
 8.6 6.4 [email protected]

Weakness enumeration for CVE-2017-3203

GitHub Security Advisory for CVE-2017-3203

GHSA-8v4h-j42h-wfhc · Severity: high · Ecosystem: maven — Deserialization of Untrusted Data in Spring-flex

Affected software / configurations for CVE-2017-3203

Vendor Product Version Raw CPE
pivotal spring-flex — cpe:2.3:a:pivotal:spring-flex:*:*:*:*:*:*:*:*

References for CVE-2017-3203

URL Tags
http://www.securityweek.com/flaws-java-amf-libraries-allow-remote-code-execution Third Party Advisory
https://codewhitesec.blogspot.com/2017/04/amf.html Exploit Mitigation Third Party Advisory
https://www.kb.cert.org/vuls/id/307983 Third Party Advisory US Government Resource
https://www.securityfocus.com/bid/97376 Third Party Advisory VDB Entry
cvelogic Threat Intelligence