Cyber Resilience

CVE-2020-3187

Path Traversal in Cisco Adaptive Security Appliance Software 9.6 – 9.6.4.40

Public PoCHigh EPSSPath Traversal
Published
06 May 2020
Modified
21 November 2024
Patch / advisory
CVSS Score v3.1 9.1
Click a component to see what it means
Raw vectorCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
EPSS Score 0.97 99.9th percentile
Risk Priority 92 floored blend · peak EPSS

Summary

CVE-2020-3187 is a critical-severity Path Traversal (CWE-22) vulnerability in Cisco Adaptive Security Appliance Software. Its CVSS base score is 9.1 (Critical).

Operationally, ranked in the top 0.1% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.

OWASP Top 10 for Web (2025)

EU & UK References

Vulnerability Data

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 obtain read and delete access to sensitive…

more

files on a targeted system. The vulnerability is due to a lack of proper input validation of the HTTP URL. An attacker could exploit this vulnerability by sending a crafted HTTP request containing directory traversal character sequences. An exploit could allow the attacker to view or delete arbitrary files on the targeted system. When the device is reloaded after exploitation of this vulnerability, any files that were deleted are restored. The attacker can only view and delete files within the web services file system. This file system is enabled when the affected device is configured with either WebVPN or AnyConnect features. This vulnerability can not be used to obtain access to ASA or FTD system files or underlying operating system (OS) files. Reloading the affected device will restore all files within the web services file system.

CWE(s)

Related Threats

Likely ATT&CK TechniquesAI

Techniques this vulnerability likely enables, inferred from its description, weakness type, and attributed-actor tradecraft. Confidence is per-technique.

T1190 Exploit Public-Facing Application Initial Accessconfidence: HIGH
Unauthenticated remote attacker exploits improper input validation in the web services interface via crafted HTTP requests to read/delete files.
T1083 File and Directory Discovery Discoveryconfidence: MEDIUM
Directory traversal allows enumeration and access to files within the web services file system.
T1005 Data from Local System Collectionconfidence: MEDIUM
Successful exploitation grants read access to arbitrary files in the web services file system.
inferred from description + CWE · MITRE ATT&CK Enterprise v19.0

CVEs Like This One

CVE-2020-3452Same product: Cisco Adaptive Security Appliance Software
CVE-2026-20148Same vendor: Cisco
CVE-2025-20187Same vendor: Cisco
CVE-2025-20277Same vendor: Cisco
CVE-2025-20344Same vendor: Cisco
CVE-2024-20532Same vendor: Cisco
CVE-2024-20528Same vendor: Cisco
CVE-2024-20529Same vendor: Cisco
CVE-2015-0666Same vendor: Cisco
CVE-2025-20374Same vendor: Cisco

Affected Assets

cisco
firepower threat defense
6.2.3 — 6.2.3.16 · 6.3.0 — 6.3.0.6 · 6.4.0 — 6.4.0.8
cisco
asa 5505 firmware
9.6\(4\)
cisco
asa 5510 firmware
9.6\(4\)
cisco
asa 5512-x firmware
9.6\(4\)
cisco
asa 5515-x firmware
9.6\(4\)
cisco
asa 5520 firmware
9.6\(4\)
cisco
asa 5525-x firmware
9.6\(4\)
cisco
asa 5540 firmware
9.6\(4\)
cisco
asa 5545-x firmware
9.6\(4\)
cisco
asa 5550 firmware
9.6\(4\)
+4 more product configuration(s) — see NVD for full list

Mitigating Controls

Control response

Prevent
Stop it (NIST 800-53)

Detect
Catch it (NIST detect / respond)

Harden
Shrink the surface (DISA STIG)

Validate
Prove the fix (OWASP ASVS)
  • V5.3.2

Likely Mitigating Controls AI

Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.

addresses: CWE-22

Validates pathnames and filenames to prevent traversal outside intended directories.

Mitigating Controls (NIST CSF 2.0) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.

PR.PS-02 partial match
prevents

Patching/maintenance can remediate known path-traversal flaws in deployed software (partial prevention of exploitability) but does nothing to stop the coding defect from being introduced in the first place.

PR.AA-05 none match
prevents

PR.AA-05 defines and reviews access policies but does not address code-level pathname neutralization, so neither direction prevents CWE-22.

Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.

detects

Security testing in development catches path traversal via static/dynamic analysis.

prevents

Secure SDLC mandates input validation and path sanitization that directly prevent path traversal.

prevents

Application security requirements include rules for safe file handling and canonicalization.

prevents

Secure architecture principles require least-privilege file access and directory isolation.

prevents

Secure coding standards explicitly forbid unsafe path construction and mandate safe APIs.

mitigates

Information access restriction limits which files an application may read or write.

References