CVE-2020-3133

Cisco Email Security Appliance Content Filter Bypass Vulnerability

HIGH
7.5
CVSS Score
Published: September 23, 2020 at 12:25 AM UTC
Updated: June 17, 2026 at 03:17 AM UTC
1 product affected across 1 vendorEmail Security Appliance

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Severity
HIGH7.5
Exploit prediction
EPSS 1%
SSVC
No known exploit

Description

A vulnerability in the email message scanning of Cisco AsyncOS Software for Cisco Email Security Appliance (ESA) could allow an unauthenticated, remote attacker to bypass configured filters on the device. The vulnerability is due to improper validation of incoming emails. An attacker could exploit this vulnerability by sending a crafted email message to a recipient protected by the ESA. A successful exploit could allow the attacker to bypass the configured content filters, which could allow malicious content to pass through the device.

Affected

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

v < 13.0
Affected range stops below 13.0, so it looks safe — our inference, not a vendor statement

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
UNCHANGED
Confidentiality
NONE
Integrity
HIGH
Availability
NONE
Vector?

Quick Info

StatusMODIFIED
CWE
CWE-20

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