How severe is CVE-2016-8738?

CVE-2016-8738 has a CVSS 3.x base score of 5.9, rated medium severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2016-8738 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (87th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2016-8738?

CVE-2016-8738 primarily affects Apache Struts. In total, 6 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2016-8738?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2016-8738 published?

CVE-2016-8738 was published on 2017-09-20 and last updated on 2026-06-17.

CVE-2016-8738

CVE-2016-8738 is a medium-severity vulnerability in Apache Struts with a CVSS 3.x base score of 5.9. 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: Medium (CVSS 3.x base score 5.9)
CVSS v2: 4.3
EPSS exploit prediction: 3% (87th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-20
Affected product: Apache Struts
Published: 2017-09-20
Last modified: 2026-06-17

Description

In Apache Struts 2.5 through 2.5.5, if an application allows entering a URL in a form field and the built-in URLValidator is used, it is possible to prepare a special URL which will be used to overload server process when performing validation of the URL.

Frequently asked questions

What is CVE-2016-8738?: In Apache Struts 2.5 through 2.5.5, if an application allows entering a URL in a form field and the built-in URLValidator is used, it is possible to prepare a special URL which will be used to overload server process when performing validation of the URL.
How severe is CVE-2016-8738?: CVE-2016-8738 has a CVSS 3.x base score of 5.9, rated medium severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2016-8738 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (87th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2016-8738?: CVE-2016-8738 primarily affects Apache Struts. In total, 6 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2016-8738?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2016-8738 published?: CVE-2016-8738 was published on 2017-09-20 and last updated on 2026-06-17.

References

Affected products (6)

cpe:2.3:a:apache:struts:2.5:*:*:*:*:*:*:*
cpe:2.3:a:apache:struts:2.5.1:*:*:*:*:*:*:*
cpe:2.3:a:apache:struts:2.5.2:*:*:*:*:*:*:*
cpe:2.3:a:apache:struts:2.5.3:*:*:*:*:*:*:*
cpe:2.3:a:apache:struts:2.5.4:*:*:*:*:*:*:*
cpe:2.3:a:apache:struts:2.5.5:*:*:*:*:*:*:*

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