How severe is CVE-2016-4438?

CVE-2016-4438 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2016-4438 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 17% (97th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2016-4438?

CVE-2016-4438 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-2016-4438?

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

When was CVE-2016-4438 published?

CVE-2016-4438 was published on 2016-07-04 and last updated on 2026-06-17.

CVE-2016-4438

CVE-2016-4438 is a critical-severity vulnerability in Apache Struts with a CVSS 3.x base score of 9.8. Its EPSS exploit-prediction score of 17% places it in the 97th percentile, indicating an elevated likelihood of exploitation. The underlying weakness is classified as CWE-20.

Key facts

Severity: Critical (CVSS 3.x base score 9.8)
CVSS v2: 7.5
EPSS exploit prediction: 17% (97th 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

The REST plugin in Apache Struts 2 2.3.19 through 2.3.28.1 allows remote attackers to execute arbitrary code via a crafted expression.

Frequently asked questions

What is CVE-2016-4438?: The REST plugin in Apache Struts 2 2.3.19 through 2.3.28.1 allows remote attackers to execute arbitrary code via a crafted expression.
How severe is CVE-2016-4438?: CVE-2016-4438 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2016-4438 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 17% (97th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2016-4438?: CVE-2016-4438 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-2016-4438?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
When was CVE-2016-4438 published?: CVE-2016-4438 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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