How severe is CVE-2017-3203?

CVE-2017-3203 has a CVSS 3.x base score of 8.1, rated high severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2017-3203 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 6% (93rd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2017-3203?

CVE-2017-3203 affects Pivotal Spring-flex. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2017-3203?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

When was CVE-2017-3203 published?

CVE-2017-3203 was published on 2018-06-11 and last updated on 2026-06-17.

CVE-2017-3203

CVE-2017-3203 is a high-severity vulnerability in Pivotal Spring-flex with a CVSS 3.x base score of 8.1. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-502.

Key facts

Severity: High (CVSS 3.x base score 8.1)
CVSS v2: 6.8
EPSS exploit prediction: 6% (93rd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-502
Affected product: Pivotal Spring-flex
Published: 2018-06-11
Last modified: 2026-06-17

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.

Frequently asked questions

What is CVE-2017-3203?: 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.
How severe is CVE-2017-3203?: CVE-2017-3203 has a CVSS 3.x base score of 8.1, rated high severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2017-3203 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 6% (93rd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2017-3203?: CVE-2017-3203 affects Pivotal Spring-flex. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2017-3203?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2017-3203 published?: CVE-2017-3203 was published on 2018-06-11 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:pivotal:spring-flex:*:*:*:*:*:*:*:*

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