How severe is CVE-2017-12165?

CVE-2017-12165 has a CVSS 3.x base score of 2.6, rated low severity. It is exploitable over network with high attack complexity, requires low privileges and user interaction. Impact on confidentiality is none, integrity low, and availability none.

Is CVE-2017-12165 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (77th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2017-12165?

CVE-2017-12165 primarily affects Redhat Undertow. In total, 4 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2017-12165?

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

When was CVE-2017-12165 published?

CVE-2017-12165 was published on 2018-07-27 and last updated on 2026-06-17.

CVE-2017-12165

CVE-2017-12165 is a low-severity vulnerability in Redhat Undertow with a CVSS 3.x base score of 2.6. 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-444.

Key facts

Severity: Low (CVSS 3.x base score 2.6)
CVSS v2: 5.0
EPSS exploit prediction: 2% (77th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-444
Affected product: Redhat Undertow
Published: 2018-07-27
Last modified: 2026-06-17

Description

It was discovered that Undertow before 1.4.17, 1.3.31 and 2.0.0 processes http request headers with unusual whitespaces which can cause possible http request smuggling.

Frequently asked questions

What is CVE-2017-12165?: It was discovered that Undertow before 1.4.17, 1.3.31 and 2.0.0 processes http request headers with unusual whitespaces which can cause possible http request smuggling.
How severe is CVE-2017-12165?: CVE-2017-12165 has a CVSS 3.x base score of 2.6, rated low severity. It is exploitable over network with high attack complexity, requires low privileges and user interaction. Impact on confidentiality is none, integrity low, and availability none.
Is CVE-2017-12165 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (77th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2017-12165?: CVE-2017-12165 primarily affects Redhat Undertow. In total, 4 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2017-12165?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2017-12165 published?: CVE-2017-12165 was published on 2018-07-27 and last updated on 2026-06-17.

References

Affected products (4)

cpe:2.3:a:redhat:undertow:*:*:*:*:*:*:*:*
cpe:2.3:a:redhat:undertow:2.0.0:alpha_1:*:*:*:*:*:*
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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