How severe is CVE-2017-6056?

CVE-2017-6056 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-2017-6056 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 7% (94th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2017-6056?

CVE-2017-6056 primarily affects Canonical Ubuntu Linux. In total, 3 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2017-6056?

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-2017-6056 published?

CVE-2017-6056 was published on 2017-02-17 and last updated on 2026-06-17.

CVE-2017-6056

CVE-2017-6056 is a high-severity vulnerability in Canonical Ubuntu Linux 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: 7% (94th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-835
Affected product: Canonical Ubuntu Linux
Published: 2017-02-17
Last modified: 2026-06-17

Description

It was discovered that a programming error in the processing of HTTPS requests in the Apache Tomcat servlet and JSP engine may result in denial of service via an infinite loop. The denial of service is easily achievable as a consequence of backporting a CVE-2016-6816 fix but not backporting the fix for Tomcat bug 57544. Distributions affected by this backporting issue include Debian (before 7.0.56-3+deb8u8 and 8.0.14-1+deb8u7 in jessie) and Ubuntu.

Frequently asked questions

What is CVE-2017-6056?: It was discovered that a programming error in the processing of HTTPS requests in the Apache Tomcat servlet and JSP engine may result in denial of service via an infinite loop. The denial of service is easily achievable as a consequence of backporting a CVE-2016-6816 fix but not backporting the fix for Tomcat bug 57544. Distributions affected by this backporting issue include Debian (before 7.0.56-3+deb8u8 and 8.0.14-1+deb8u7 in jessie) and Ubuntu.
How severe is CVE-2017-6056?: CVE-2017-6056 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-2017-6056 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 7% (94th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2017-6056?: CVE-2017-6056 primarily affects Canonical Ubuntu Linux. In total, 3 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2017-6056?: 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-2017-6056 published?: CVE-2017-6056 was published on 2017-02-17 and last updated on 2026-06-17.

References

Affected products (3)

cpe:2.3:o:canonical:ubuntu_linux:12.04:*:*:*:lts:*:*:*
cpe:2.3:o:canonical:ubuntu_linux:14.04:*:*:*:lts:*:*:*
cpe:2.3:o:debian:debian_linux:8.0:*:*:*:*:*:*:*

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