How severe is CVE-2016-5396?

CVE-2016-5396 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-2016-5396 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (85th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2016-5396?

CVE-2016-5396 primarily affects Apache Traffic Server. In total, 4 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2016-5396?

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-2016-5396 published?

CVE-2016-5396 was published on 2017-04-17 and last updated on 2026-06-17.

CVE-2016-5396

CVE-2016-5396 is a high-severity vulnerability in Apache Traffic Server 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-399.

Key facts

Severity: High (CVSS 3.x base score 7.5)
CVSS v2: 7.8
EPSS exploit prediction: 3% (85th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-399
Affected product: Apache Traffic Server
Published: 2017-04-17
Last modified: 2026-06-17

Description

Apache Traffic Server 6.0.0 to 6.2.0 are affected by an HPACK Bomb Attack.

Frequently asked questions

What is CVE-2016-5396?: Apache Traffic Server 6.0.0 to 6.2.0 are affected by an HPACK Bomb Attack.
How severe is CVE-2016-5396?: CVE-2016-5396 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-2016-5396 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (85th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2016-5396?: CVE-2016-5396 primarily affects Apache Traffic Server. In total, 4 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2016-5396?: 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-2016-5396 published?: CVE-2016-5396 was published on 2017-04-17 and last updated on 2026-06-17.

References

Affected products (4)

cpe:2.3:a:apache:traffic_server:6.0.0:*:*:*:*:*:*:*
cpe:2.3:a:apache:traffic_server:6.1.0:*:*:*:*:*:*:*
cpe:2.3:a:apache:traffic_server:6.1.1:*:*:*:*:*:*:*
cpe:2.3:a:apache:traffic_server:6.2.0:*:*:*:*:*:*:*

More vulnerabilities in Apache Traffic Server

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CVE-2019-17565 — Critical (CVSS 9.8): There is a vulnerability in Apache Traffic Server 6.0.0 to 6.2.3, 7.0.0 to 7.1.8, and 8.0.0 to 8.0.5 with a smuggling…
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Other CWE-399 (Resource Management Errors) vulnerabilities

CVE-2015-8104 — Critical (CVSS 10.0): The KVM subsystem in the Linux kernel through 4.2.6, and Xen 4.3.x through 4.6.x, allows guest OS users to cause a…
CVE-2015-0339 — Critical (CVSS 10.0): Adobe Flash Player before 13.0.0.277 and 14.x through 17.x before 17.0.0.134 on Windows and OS X and before…
CVE-2015-0335 — Critical (CVSS 10.0): Adobe Flash Player before 13.0.0.277 and 14.x through 17.x before 17.0.0.134 on Windows and OS X and before…
CVE-2015-0333 — Critical (CVSS 10.0): Adobe Flash Player before 13.0.0.277 and 14.x through 17.x before 17.0.0.134 on Windows and OS X and before…
CVE-2014-4121 — Critical (CVSS 10.0): Microsoft .NET Framework 2.0 SP2, 3.5, 3.5.1, 4, 4.5, 4.5.1, and 4.5.2 does not properly parse internationalized…
CVE-2014-0560 — Critical (CVSS 10.0): Use-after-free vulnerability in Adobe Reader and Acrobat 10.x before 10.1.12 and 11.x before 11.0.09 on Windows and OS…

Browse all CWE-399 (Resource Management Errors) vulnerabilities →