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CVE Record

CVE-2018-0447: Cisco Email Security Appliance URL Filtering Bypass Vulnerability

A vulnerability in the anti-spam protection mechanisms of Cisco AsyncOS Software for the Cisco Email Security Appliance (ESA) could allow an unauthenticated, remote attacker to bypass certain content filters on an affected device. The vulnerability is due to incomplete input and validation checking mechanisms for certain Sender Policy Framework (SPF) messages that are sent to an affected device. An attacker could exploit this vulnerability by sending a customized SPF packet to an affected device. If successful, an exploit could allow the attacker to bypass the URL filters that are configured for the affected device, which could allow malicious URLs to pass through the device.

UnknownCVSS not scoredNot KEV-listedUpdated
Glexia's TakeAutomated analysis

Security readout for executives and security teams

This issue could let an external sender bypass Cisco ESA URL filtering, allowing links that should be blocked to reach users. The available source bundle does not provide severity scoring, affected version detail, or confirmed exploitation evidence. Organizations using Cisco ESA with URL filtering enabled may be exposed. The source bundle does not identify affected AsyncOS versions, deployment conditions, or vulnerable configurations beyond Cisco ESA. Treat this as a practical email-security control bypass, not a confirmed crisis. Prioritize checking exposure because successful abuse could increase phishing risk reaching employees. Mitigation focus: Review Cisco's advisory for affected releases and vendor remediation guidance.; Apply Cisco-recommended updates or workarounds if your ESA release is affected.; Confirm URL filtering is not the only control for malicious-link defense..

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CVE-2018-0447 mapping review

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Vulnerability profileCVE Program record
Severity
Unknown
CVSS
Not scored
Known Exploited
No
Published
Official CVE source material

CNA and ADP enrichment extracted from CVE v5

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0CVSS vectors
0Timeline events
0ADP providers
2Source links

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Source materials

Affected products

Products and packages named in the record

VendorProductVersion / packageStatus
CiscoCisco Email Security Appliance (ESA)n/aListed
Weakness

CWE details

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