How severe is CVE-2020-10687?

CVE-2020-10687 has a CVSS 3.x base score of 4.8, rated medium severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is low, integrity low, and availability none.

Is CVE-2020-10687 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (63rd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2020-10687?

CVE-2020-10687 primarily affects Redhat Undertow. In total, 6 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2020-10687?

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

When was CVE-2020-10687 published?

CVE-2020-10687 was published on 2020-09-23 and last updated on 2026-06-17.

CVE-2020-10687

CVE-2020-10687 is a medium-severity vulnerability in Redhat Undertow with a CVSS 3.x base score of 4.8. 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-444.

Key facts

Severity: Medium (CVSS 3.x base score 4.8)
CVSS v2: 5.8
EPSS exploit prediction: 1% (63rd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-444
Affected product: Redhat Undertow
Published: 2020-09-23
Last modified: 2026-06-17

Description

A flaw was discovered in all versions of Undertow before Undertow 2.2.0.Final, where HTTP request smuggling related to CVE-2017-2666 is possible against HTTP/1.x and HTTP/2 due to permitting invalid characters in an HTTP request. This flaw allows an attacker to poison a web-cache, perform an XSS attack, or obtain sensitive information from request other than their own.

Frequently asked questions

What is CVE-2020-10687?: A flaw was discovered in all versions of Undertow before Undertow 2.2.0.Final, where HTTP request smuggling related to CVE-2017-2666 is possible against HTTP/1.x and HTTP/2 due to permitting invalid characters in an HTTP request. This flaw allows an attacker to poison a web-cache, perform an XSS attack, or obtain sensitive information from request other than their own.
How severe is CVE-2020-10687?: CVE-2020-10687 has a CVSS 3.x base score of 4.8, rated medium severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is low, integrity low, and availability none.
Is CVE-2020-10687 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (63rd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2020-10687?: CVE-2020-10687 primarily affects Redhat Undertow. In total, 6 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2020-10687?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2020-10687 published?: CVE-2020-10687 was published on 2020-09-23 and last updated on 2026-06-17.

References

Affected products (6)

cpe:2.3:a:redhat:undertow:*:*:*:*:*:*:*:*
cpe:2.3:a:redhat:jboss_enterprise_application_platform:-:*:*:*:text-only:*:*:*
cpe:2.3:a:redhat:single_sign-on:-:*:*:*:text-only:*:*:*
cpe:2.3:a:redhat:jboss_enterprise_application_platform:7.2:*:*:*:*:*:*:*
cpe:2.3:a:redhat:jboss_enterprise_application_platform:7.3:*:*:*:*:*:*:*
cpe:2.3:a:redhat:jboss_enterprise_application_platform:7.4:*:*:*:*:*:*:*

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