How severe is CVE-2020-3317?

CVE-2020-3317 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-2020-3317 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (57th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2020-3317?

CVE-2020-3317 affects Cisco Firepower Threat Defense. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2020-3317?

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-2020-3317 published?

CVE-2020-3317 was published on 2020-10-21 and last updated on 2026-06-17.

CVE-2020-3317

CVE-2020-3317 is a high-severity vulnerability in Cisco Firepower Threat Defense 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: 1% (57th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-20
Affected product: Cisco Firepower Threat Defense
Published: 2020-10-21
Last modified: 2026-06-17

Description

A vulnerability in the ssl_inspection component of Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to crash Snort instances. The vulnerability is due to insufficient input validation in the ssl_inspection component. An attacker could exploit this vulnerability by sending a malformed TLS packet through a Cisco Adaptive Security Appliance (ASA). A successful exploit could allow the attacker to crash a Snort instance, resulting in a denial of service (DoS) condition.

Frequently asked questions

What is CVE-2020-3317?: A vulnerability in the ssl_inspection component of Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to crash Snort instances. The vulnerability is due to insufficient input validation in the ssl_inspection component. An attacker could exploit this vulnerability by sending a malformed TLS packet through a Cisco Adaptive Security Appliance (ASA). A successful exploit could allow the attacker to crash a Snort instance, resulting in a denial of service (DoS) condition.
How severe is CVE-2020-3317?: CVE-2020-3317 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-2020-3317 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (57th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2020-3317?: CVE-2020-3317 affects Cisco Firepower Threat Defense. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2020-3317?: 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-2020-3317 published?: CVE-2020-3317 was published on 2020-10-21 and last updated on 2026-06-17.

References

https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-ftd-ssl-mf3822Z

Affected products (1)

cpe:2.3:a:cisco:firepower_threat_defense:*:*:*:*:*:*:*:*

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