How severe is CVE-2017-2670?

CVE-2017-2670 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 none, and availability high.

Is CVE-2017-2670 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 4% (88th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2017-2670?

CVE-2017-2670 primarily affects Redhat Undertow. In total, 5 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2017-2670?

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-2017-2670 published?

CVE-2017-2670 was published on 2018-07-27 and last updated on 2026-06-17.

CVE-2017-2670

CVE-2017-2670 is a high-severity vulnerability in Redhat Undertow 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-835.

Key facts

Severity: High (CVSS 3.x base score 7.5)
CVSS v2: 5.0
EPSS exploit prediction: 4% (88th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-835
Affected product: Redhat Undertow
Published: 2018-07-27
Last modified: 2026-06-17

Description

It was found in Undertow before 1.3.28 that with non-clean TCP close, the Websocket server gets into infinite loop on every IO thread, effectively causing DoS.

Frequently asked questions

What is CVE-2017-2670?: It was found in Undertow before 1.3.28 that with non-clean TCP close, the Websocket server gets into infinite loop on every IO thread, effectively causing DoS.
How severe is CVE-2017-2670?: CVE-2017-2670 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 none, and availability high.
Is CVE-2017-2670 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 4% (88th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2017-2670?: CVE-2017-2670 primarily affects Redhat Undertow. In total, 5 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2017-2670?: 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-2017-2670 published?: CVE-2017-2670 was published on 2018-07-27 and last updated on 2026-06-17.

References

Affected products (5)

cpe:2.3:a:redhat:undertow:*:*:*:*:*:*:*:*
cpe:2.3:o:debian:debian_linux:9.0:*:*:*:*:*:*:*
cpe:2.3:a:redhat:jboss_enterprise_application_platform:6.0.0:*:*:*:*:*:*:*
cpe:2.3:a:redhat:jboss_enterprise_application_platform:7.0.0:*:*:*:*:*:*:*
cpe:2.3:a:redhat:jboss_enterprise_application_platform:7.1.0:*:*:*:*:*:*:*

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