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CVE-2017-3814 Cisco CVE debrief

CVE-2017-3814 is a Cisco URL bypass issue that could let an unauthenticated remote attacker evade web-content blocking controls on affected Firepower software. NVD rates it CVSS 5.8 (Medium), with network reachability and no authentication required, so organizations that depend on Cisco URL filtering should treat it as a control-enforcement weakness rather than a code-execution event.

Vendor
Cisco
Product
CVE-2017-3814
CVSS
MEDIUM 5.8
CISA KEV
Not listed in stored evidence
Original CVE published
2017-02-03
Original CVE updated
2026-05-13
Advisory published
2017-02-03
Advisory updated
2026-05-13

Who should care

Cisco administrators and security teams running affected Firepower System Software or the Secure Firewall Management Center versions listed by NVD, especially environments that rely on URL filtering or web content blocking for policy enforcement.

Technical summary

The published description states that a remote, unauthenticated attacker could maliciously bypass the appliance's ability to block certain web content (a URL bypass). NVD maps the issue to Cisco Secure Firewall Management Center CPEs for versions 5.3.0, 5.4.0, 6.0.0, 6.0.1, and 6.1.0, and assigns CWE-20 (Improper Input Validation). The CVSS v3.0 vector is AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:N/A:N, indicating a network-reachable issue with limited confidentiality impact and no integrity or availability impact in the base score.

Defensive priority

Medium. Prioritize if your environment uses Cisco content-filtering or URL-blocking policy as a security control, because the impact is policy bypass rather than service disruption.

Recommended defensive actions

  • Check whether any deployed Cisco Firepower or Secure Firewall Management Center systems match the affected versions listed by NVD.
  • Review the Cisco security advisory and apply Cisco's recommended fixed release or mitigation guidance for your deployed product branch.
  • Validate that URL filtering and web-content blocking policies still enforce as expected after remediation.
  • Review logs and policy exceptions for evidence of unexpected URL access that may indicate control bypass behavior.
  • If immediate patching is not possible, apply compensating controls documented by Cisco and restrict exposure of administrative and management interfaces where appropriate.

Evidence notes

This debrief is based on the CVE description, NVD metadata, and Cisco references supplied in the source corpus. The key evidence points are: unauthenticated remote URL bypass; affected versions 5.3.0, 5.4.0, 6.0.0, 6.0.1, and 6.1.0; CVSS 5.8/Medium; CVSS vector AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:N/A:N; and CWE-20. Published date used for timing context is 2017-02-03, with NVD last modified on 2026-05-13.

Official resources

Publicly disclosed in the CVE/NVD record on 2017-02-03; NVD metadata was last modified on 2026-05-13.