CVE-2020-3283

Cisco Firepower 1000 Series SSL/TLS Denial of Service Vulnerability

HIGH
8.6
CVSS Score
Published: May 6, 2020 at 04:41 PM UTC
Updated: August 11, 2026 at 07:33 PM UTC
29 products affected across 1 vendorSecure Firewall Threat DefenseASA 5512-x FirmwareASA 5515-x Firmware

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Severity
HIGH8.6
Exploit prediction
EPSS 2%
SSVC
No known exploit

Description

A vulnerability in the Secure Sockets Layer (SSL)/Transport Layer Security (TLS) handler of Cisco Firepower Threat Defense (FTD) Software when running on the Cisco Firepower 1000 Series platform could allow an unauthenticated, remote attacker to trigger a denial of service (DoS) condition on an affected device. The vulnerability is due to a communication error between internal functions. An attacker could exploit this vulnerability by sending a crafted SSL/TLS message to an affected device. A successful exploit could allow the attacker to cause a buffer underrun, which leads to a crash. The crash causes the affected device to reload.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

cisco-asa-5505 (same device)
cisco-asa-5510 (same device)
cisco-asa-5512-x (same device)
cisco-asa-5515-x (same device)
cisco-asa-5520 (same device)
cisco-asa-5525-x (same device)
cisco-asa-5540 (same device)
cisco-asa-5545-x (same device)
cisco-asa-5550 (same device)
cisco-asa-5555-x (same device)

Remediation

No guide yet

No remediation guidance has been written for this CVE yet. What the record does show:

SSVC — Action Prioritization

SSVCNo known exploitAutomatablePartial impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

Attack Vector
NETWORK
Complexity
LOW
Privileges
NONE
User Interaction
NONE
Scope
CHANGED
Confidentiality
NONE
Integrity
NONE
Availability
HIGH
Vector?

Quick Info

StatusMODIFIED
CWE
CWE-119CWE-787

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