How severe is CVE-2016-4800?

CVE-2016-4800 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-2016-4800 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-2016-4800?

CVE-2016-4800 primarily affects Eclipse Jetty. In total, 19 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2016-4800?

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-2016-4800 published?

CVE-2016-4800 was published on 2017-04-13 and last updated on 2026-06-17.

CVE-2016-4800

CVE-2016-4800 is a critical-severity vulnerability in Eclipse Jetty with a CVSS 3.x base score of 9.8. 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-284.

Key facts

Severity: Critical (CVSS 3.x base score 9.8)
CVSS v2: 7.5
EPSS exploit prediction: 6% (93rd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-284
Affected product: Eclipse Jetty
Published: 2017-04-13
Last modified: 2026-06-17

Description

The path normalization mechanism in PathResource class in Eclipse Jetty 9.3.x before 9.3.9 on Windows allows remote attackers to bypass protected resource restrictions and other security constraints via a URL with certain escaped characters, related to backslashes.

Frequently asked questions

What is CVE-2016-4800?: The path normalization mechanism in PathResource class in Eclipse Jetty 9.3.x before 9.3.9 on Windows allows remote attackers to bypass protected resource restrictions and other security constraints via a URL with certain escaped characters, related to backslashes.
How severe is CVE-2016-4800?: CVE-2016-4800 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-2016-4800 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-2016-4800?: CVE-2016-4800 primarily affects Eclipse Jetty. In total, 19 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2016-4800?: 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-2016-4800 published?: CVE-2016-4800 was published on 2017-04-13 and last updated on 2026-06-17.

References

Affected products (19)

cpe:2.3:a:eclipse:jetty:9.3.0:*:*:*:*:*:*:*
cpe:2.3:a:eclipse:jetty:9.3.0:m0:*:*:*:*:*:*
cpe:2.3:a:eclipse:jetty:9.3.0:m1:*:*:*:*:*:*
cpe:2.3:a:eclipse:jetty:9.3.0:maintenance2:*:*:*:*:*:*
cpe:2.3:a:eclipse:jetty:9.3.0:rc0:*:*:*:*:*:*
cpe:2.3:a:eclipse:jetty:9.3.0:rc1:*:*:*:*:*:*
cpe:2.3:a:eclipse:jetty:9.3.1:*:*:*:*:*:*:*
cpe:2.3:a:eclipse:jetty:9.3.2:*:*:*:*:*:*:*
cpe:2.3:a:eclipse:jetty:9.3.3:*:*:*:*:*:*:*
cpe:2.3:a:eclipse:jetty:9.3.4:*:*:*:*:*:*:*
cpe:2.3:a:eclipse:jetty:9.3.4:rc0:*:*:*:*:*:*
cpe:2.3:a:eclipse:jetty:9.3.4:rc1:*:*:*:*:*:*
cpe:2.3:a:eclipse:jetty:9.3.5:*:*:*:*:*:*:*
cpe:2.3:a:eclipse:jetty:9.3.6:*:*:*:*:*:*:*
cpe:2.3:a:eclipse:jetty:9.3.7:*:*:*:*:*:*:*
cpe:2.3:a:eclipse:jetty:9.3.7:rc0:*:*:*:*:*:*
cpe:2.3:a:eclipse:jetty:9.3.7:rc1:*:*:*:*:*:*
cpe:2.3:a:eclipse:jetty:9.3.8:*:*:*:*:*:*:*
cpe:2.3:a:eclipse:jetty:9.3.8:rc0:*:*:*:*:*:*

More vulnerabilities in Eclipse Jetty

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All CVEs affecting Eclipse Jetty →

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CVE-2026-58630 — Critical (CVSS 10.0): Improper access control in Azure App Service allows an unauthorized attacker to elevate privileges over a network.
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Browse all CWE-284 (Improper Access Control) vulnerabilities →

Threat intelligence

Threat-intel indicators referencing this CVE:

47.236.247.176 (ipv4-addr)
60.227.234.109 (ipv4-addr)
8.211.195.173 (ipv4-addr)