Vulnerability report

Active exploitation observed Confirmed confidence In CISA KEV

CVE-2020-3452

Cisco Adaptive Security Appliance (ASA) Software Path Traversal

Cisco Adaptive Security Appliance (ASA) Software · affected before 9.6.4.42

Watch CVE-2020-3452 Browse KEV feed
Severity
CVSS 7.5 · High
Confidence
Confirmed
Exploit status
Observed in sensors
EPSS
100.0%
First observed
29 Jun 2026
Last observed
08 Oct 2026

Decision summary

What security teams need to know first

Direct answers before the deeper technical record.

What it is

CVE-2020-3452 is an unauthenticated vulnerability affecting Cisco Adaptive Security Appliance (ASA) Software. A vulnerability in the web services interface of Cisco Adaptive Security Appliance (ASA) Software and Cisco...

Is it exploited?

Yes. Previdian sensors observed exploitation attempts with confirmed confidence. Listed in CISA KEV. Also confirmed by third-party sources.

Who is affected?

Cisco Adaptive Security Appliance (ASA) Software affected before 9.6.4.42.

What should we do?

Patch immediately, validate internet-facing exposure, and monitor for matching requests.

Overview

Cisco Adaptive Security Appliance (ASA) Software Path Traversal

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.

Cisco Affected
Cisco Adaptive Security Appliance (ASA) Software
Before 9.6.4.42 Before 9.8.4.20 Before 9.9.2.74 Before 9.10.1.42 Before 9.13.1.10 Before 9.14.1.10
View vendor advisory (opens in new tab)
Published
22 Jul 2020
Exploitation Reported
03 Nov 2021
Attack vector
Remote
Complexity
Low
Privileges
None
User interaction
None

Tags

edge cisa nuclei_scanner

CVE References

Exploitation evidence

Why Previdian marks this CVE as exploited

Third-party attestation and first-party sensor observation are shown separately so teams can judge the evidence chain.

Exploited in the wild

CISA

Recorded 03 Nov 2021

A trusted third party reported exploitation.

Active exploitation observed

Previdian sensor

First observed 29 Jun 2026

Previdian first observed exploitation attempts targeting this vulnerability in our honeypot sensors.

Proof of concept available

GitHub

Recorded 24 Jul 2020

Public scanner or PoC coverage increases practical exploitability.

Known exploited vulnerability sources

Per-source evidence links for KEV attestations are available through the Previdian Pro API.

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Source Added
CISA First 2021-11-03 00:00 UTC
The Shadowserver 2026-06-01 00:00 UTC
Previdian Sensors 2026-07-27 14:23 UTC

Operational indicators for this CVE are listed under Detection.

Sensor telemetry

First-party evidence of exploitation activity

Previdian sensors recorded exploitation attempts targeting this vulnerability. The cards and chart show volume, unique attackers, and daily activity.

515

Attempts observed

303

Unique attacker IPs

10

Attacker countries

AU · BG · CA · CH · DE · GB · NL · UA · US · YE

65

Sensors observed

CVE-2020-3452 exploitation attempts over the last 91 days

Daily events observed by Previdian sensors

Updated 10 Oct 2026

19
0
0
0
0
0
0
2
0
2
0
0
0
0
1
5
16
7
14
9
1
1
0
0
0
0
8
2
0
0
5
7
8
6
7
8
7
5
1
6
6
4
0
4
0
2
1
4
1
0
0
0
0
3
6
5
9
4
11
10
7
8
3
2
0
0
4
0
0
0
4
0
0
152
0
6
11
5
10
10
8
24
16
24
1
1
0
0
2
0
0
12 Jul 31 Jul 19 Aug 7 Sep 10 Oct

First observed 29 Jun 2026 · Last observed 08 Oct 2026

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Detection

Operational artifacts and observed signals

Make the evidence actionable in scanner, SOC, and edge-control workflows.

Observed signals

Request targets
User-Agents
Callback hosts
154
12
0

Request targets and User-Agents available in Pro. Callback host details available in Enterprise.

Virtual patch status

No Previdian virtual patch is currently available. Future rules ship for ModSecurity, Cloudflare, and AWS WAF.

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Attacker IP Indicators

Attacker IP indicators observed · available in Pro and Enterprise.

Sensor-derived attacker IP indicators are available to Pro and Enterprise accounts under Detection and through the Pro API.

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Scanner Artifacts

Scanner and exploit-framework references linked to this CVE.

Scanner Reference Detected
Nuclei https://github.com/projectdiscovery/nuclei-templates/blob/main/http/cves/2020/CVE-2020-3452.yaml 25 Apr 2025

Risk and context

Severity, weaknesses, and research context

CVSS v3.1

7.5 High

Potential damage if exploited. Separate from whether attackers are using it.

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N

EPSS

100.0%

Estimated chance of exploitation in the next 30 days. Previdian's warning comes from evidence, not this score.

Weaknesses

Improper Input Validation CWE-20 Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal') CWE-22

All CVSS Scores

CVSS v3.1 7.5 High

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N

CVSS v2.0 5.0 Medium

AV:N/AC:L/Au:N/C:P/I:N/A:N

Potential Proof of Concepts

These PoCs are unverified and could contain malware. Use at your own risk.

Cisco Adaptive Security Appliance (ASA)/Firepower Threat Defense (FTD) - Local File Inclusion

nuclei · Created Unknown

Timeline

From disclosure to observed exploitation

  1. 18:59 UTC

    Indicators of compromise added (333)

    Indicators of compromise recorded

  2. 18:59 UTC

    Observed by Previdian sensors

    Evidence-backed exploitation signal

  3. 14:20 UTC

    Public PoC available

    Public proof-of-concept code published

  4. 00:00 UTC

    KEV confirmed by The Shadowserver

    Exploitation attested by an external source

  5. 00:00 UTC

    Nuclei template available

    Scanner coverage available

  6. 00:00 UTC

    Added to CISA KEV

    Listed in the CISA Known Exploited Vulnerabilities catalog

  7. 20:00 UTC

    CVE published

    Vulnerability disclosed publicly

  8. 00:00 UTC

    CVE ID reserved

    Identifier reserved by the CNA

Pro API

Automate this intelligence

Confidence, exploit status, sensor telemetry, PoCs, scanner integrations, mentions, and tags are available programmatically for VM, SOC, and CTI workflows.

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  • Evidence confidence and provenance
  • First-party sensor telemetry
  • PoC and scanner references
  • Affected versions and enrichment
  • Automation-ready JSON delivery

GET /api/v2/pro/kevs/CVE-2020-3452

Free JSON includes basic KEV fields 
{
  "cve_id": "CVE-2020-3452",
  "confidence": "Confirmed",
  "cvss_score": 7.5,
  "cvss_estimated": false,
  "epss_score": 0.99992,
  "exploit_status": {
    "exploited_in_the_wild": true,
    "active_exploitation_observed": true
  },
  "sensor_telemetry": { "attempts": 515, "sensors": 65 }
}