How severe is CVE-2016-4431?

CVE-2016-4431 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity high, and availability none.

Is CVE-2016-4431 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 10% (95th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2016-4431?

CVE-2016-4431 primarily affects Apache Struts. In total, 7 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2016-4431?

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-2016-4431 published?

CVE-2016-4431 was published on 2016-07-04 and last updated on 2026-06-17.

CVE-2016-4431

CVE-2016-4431 is a high-severity vulnerability in Apache Struts with a CVSS 3.x base score of 7.5. 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-20.

Key facts

Severity: High (CVSS 3.x base score 7.5)
CVSS v2: 5.0
EPSS exploit prediction: 10% (95th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-20
Affected product: Apache Struts
Published: 2016-07-04
Last modified: 2026-06-17

Description

Apache Struts 2 2.3.20 through 2.3.28.1 allows remote attackers to bypass intended access restrictions and conduct redirection attacks by leveraging a default method.

Frequently asked questions

What is CVE-2016-4431?: Apache Struts 2 2.3.20 through 2.3.28.1 allows remote attackers to bypass intended access restrictions and conduct redirection attacks by leveraging a default method.
How severe is CVE-2016-4431?: CVE-2016-4431 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity high, and availability none.
Is CVE-2016-4431 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 10% (95th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2016-4431?: CVE-2016-4431 primarily affects Apache Struts. In total, 7 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2016-4431?: 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-2016-4431 published?: CVE-2016-4431 was published on 2016-07-04 and last updated on 2026-06-17.

References

Affected products (7)

cpe:2.3:a:apache:struts:2.3.20:*:*:*:*:*:*:*
cpe:2.3:a:apache:struts:2.3.20.1:*:*:*:*:*:*:*
cpe:2.3:a:apache:struts:2.3.20.3:*:*:*:*:*:*:*
cpe:2.3:a:apache:struts:2.3.24:*:*:*:*:*:*:*
cpe:2.3:a:apache:struts:2.3.24.1:*:*:*:*:*:*:*
cpe:2.3:a:apache:struts:2.3.24.3:*:*:*:*:*:*:*
cpe:2.3:a:apache:struts:2.3.28:*:*:*:*:*:*:*

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