How severe is CVE-2016-9201?

CVE-2016-9201 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 high, integrity none, and availability none.

Is CVE-2016-9201 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (83rd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2016-9201?

CVE-2016-9201 affects Cisco Ios. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2016-9201?

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-2016-9201 published?

CVE-2016-9201 was published on 2016-12-14 and last updated on 2026-06-17.

CVE-2016-9201

CVE-2016-9201 is a high-severity vulnerability in Cisco Ios 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-20.

Key facts

Severity: High (CVSS 3.x base score 7.5)
CVSS v2: 5.0
EPSS exploit prediction: 3% (83rd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-20
Affected product: Cisco Ios
Published: 2016-12-14
Last modified: 2026-06-17

Description

A vulnerability in the Zone-Based Firewall feature of Cisco IOS and Cisco IOS XE Software could allow an unauthenticated, remote attacker to pass traffic that should otherwise have been dropped based on the configuration. More Information: CSCuz21015. Known Affected Releases: 15.3(3)M3. Known Fixed Releases: 15.6(2)T0.1 15.6(2.0.1a)T0 15.6(2.19)T 15.6(3)M.

Frequently asked questions

What is CVE-2016-9201?: A vulnerability in the Zone-Based Firewall feature of Cisco IOS and Cisco IOS XE Software could allow an unauthenticated, remote attacker to pass traffic that should otherwise have been dropped based on the configuration. More Information: CSCuz21015. Known Affected Releases: 15.3(3)M3. Known Fixed Releases: 15.6(2)T0.1 15.6(2.0.1a)T0 15.6(2.19)T 15.6(3)M.
How severe is CVE-2016-9201?: CVE-2016-9201 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 high, integrity none, and availability none.
Is CVE-2016-9201 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (83rd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2016-9201?: CVE-2016-9201 affects Cisco Ios. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2016-9201?: 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-2016-9201 published?: CVE-2016-9201 was published on 2016-12-14 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:o:cisco:ios:15.3\(3\)m3:*:*:*:*:*:*:*

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