+44 1865 950 828 Secure Your Business
Actively exploited

CVE-2020-3452 Cisco ASA and FTD Read-Only Path Traversal Vulnerability

Cisco Adaptive Security Appliance (ASA) and Firepower Threat Defense (FTD) contain an improper input validation vulnerability when HTTP requests process URLs. An attacker could exploit this vulnerability by sending a crafted HTTP request containing directory traversal character sequences to an affected device. A successful exploit could allow the attacker to view arbitrary files within the web services file system on the targeted device.

From the CISA KEV catalogue version 2026.11.06, with Cybergen analysis. Updated 6 Nov 2026.

Our Assessment

Should You Worry?

Patch nowCybergen assessment
  • CISA confirmed exploitation in the wild and added it to the Known Exploited Vulnerabilities catalogue on 3 Nov 2021.
  • Rated High severity (CVSS 7.5, scored by Vendor).
  • This product type is often exposed to the internet, which is where attackers scan for it first.
  • It has been in the catalogue for 1,829 days. Systems still unpatched now have almost certainly been scanned for it.
The Vulnerability

What It Is

A vulnerability in the web services interface of Cisco Adaptive Security Appliance (ASA) Software and Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to conduct directory traversal attacks and read sensitive files on a targeted system. The vulnerability is due to a lack of proper input validation of URLs in HTTP requests processed by an affected device. An attacker could exploit this vulnerability by sending a crafted HTTP request containing directory traversal character sequences to an affected device. A successful exploit could allow the attacker to view arbitrary files within the web services file system on the targeted device. The web services file system is enabled when the affected device is configured with either WebVPN or AnyConnect features. This vulnerability cannot be used to obtain access to ASA or FTD system files or underlying operating system (OS) files.

Affected Versions

ProductVersions
Cisco Cisco Adaptive Security Appliance (ASA) Softwareunspecified to before 9.6.4.42
unspecified to before 9.8.4.20
unspecified to before 9.9.2.74
unspecified to before 9.10.1.42
unspecified to before 9.13.1.10
unspecified to before 9.14.1.10

From the public CVE record, as supplied by the vendor. Always confirm against the vendor advisory.

From Watch to Action

What To Do Now

  1. 1

    Find it

    Search your asset inventory and external attack surface for Cisco Adaptive Security Appliance (ASA) and Firepower Threat Defense (FTD). Include cloud images, appliances and anything a supplier runs for you.

    Attack Surface Management
  2. 2

    Fix it

    Apply updates per vendor instructions.

    Vulnerability Management
  3. 3

    Hunt for compromise

    If an affected system was reachable before you patched, assume it may have been hit. Check logs, new accounts, web shells and outbound connections from the date of exposure.

    Incident Response
  4. 4

    Prove it is fixed

    Rescan or test the system after patching. Upgrades that fail silently and forgotten secondary instances are common.

    Penetration Testing

Vendor Advisories

Regulation

The Compliance Clock

Cyber EssentialsRated high, so if it affects devices in your Cyber Essentials scope, the update must be installed within 14 days of the vendor releasing it.NIS2If exploitation causes a significant incident, essential and important entities owe their CSIRT an early warning within 24 hours and a notification within 72 hours.DORAFinancial entities must classify ICT incidents and send an initial notification for a major incident within strict deadlines, with exploited flaws a common cause.US federal (BOD 22-01)Federal civilian agencies had until 3 May 2022 to remediate. A sensible benchmark for everyone else.

General guidance, not legal advice. Your obligations depend on your sector, scope and jurisdiction.

Stay Ahead

More Exploited Cisco Flaws

Get alerts for CiscoWe email you when a new Cisco vulnerability is confirmed as exploited. Add more vendors on Threat Watch.

By signing up you agree to receive Threat Watch alerts. Unsubscribe at any time. See our Privacy Policy.

CVE-2026-76418Cisco Secure Firewall ASA Software and Cisco Secure FTD Software Unchecked Return Value to NULL Pointer Dereference VulnerabilityAdded 29 Oct 2026CVE-2026-76519Cisco Secure Email Gateway Relative Path Traversal VulnerabilityAdded 14 Oct 2026CVE-2026-76504Cisco Catalyst SD-WAN Manager Hex Encoding VulnerabilityAdded 30 Sep 2026CVE-2026-76460Cisco Identity Services Engine Incorrect Use of Privileged APIs VulnerabilityAdded 16 Sep 2026CVE-2026-76461Cisco Secure Email Gateway SQL Injection VulnerabilityAdded 14 Sep 2026CVE-2026-20079Cisco Firewall Management Center Authentication Bypass Using an Alternate Path or Channel VulnerabilityAdded 9 Sep 2026

All 102 exploited Cisco vulnerabilities

Not Sure If You Are Exposed?

Our attack surface and vulnerability teams can check your internet-facing estate for CVE-2020-3452 and every other exploited flaw on the list.

Check My Exposure
Evidence

Sources

  1. CISA Known Exploited Vulnerabilities catalogue
  2. NVD: CVE-2020-3452
  3. CVE record: CVE-2020-3452
  4. FIRST EPSS
  5. tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-asaftd-ro-path-KJuQhB86
  6. packetstormsecurity.com/files/158646/Cisco-ASA-FTD-Remote-File-Disclosure.html
  7. packetstormsecurity.com/files/158647/Cisco-Adaptive-Security-Appliance-Software-9.11-Local-File-Incl
  8. packetstormsecurity.com/files/159523/Cisco-ASA-FTD-9.6.4.42-Path-Traversal.html
  9. packetstormsecurity.com/files/160497/Cisco-ASA-9.14.1.10-FTD-6.6.0.1-Path-Traversal.html