HOMEVULNERABILITIESCVE-2020-3187
UNKNOWNCISA KEVIN THE WILD

CVE-2020-3187

Published: April 11, 2026

EPSS:94.30%probability of exploitation in 30 daysPercentile:99.9th

Official Description

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 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.

NVD Source

Technical Analysis

CVE-2020-3187 requires local access, meaning attackers must already have a foothold on the target system.

Exploitation requires some privileges, which limits the exposure to scenarios where an attacker has already gained initial access.

CISA has added CVE-2020-3187 to the Known Exploited Vulnerabilities (KEV) catalog, confirming active exploitation in the wild. U.S. federal agencies are required to patch this within the mandated timeframe, and all organizations should treat remediation as urgent.

Affected Vendors & Products

Mentioned vendors (from description):
Cisco
CPE data not yet available in NVD for this CVE.

Exploit & PoC Resources

ACTIVE EXPLOITATIONConfirmed exploitation in the wild
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Quick Facts

CVE IDCVE-2020-3187
Severity
CISA KEVYES — Active Exploitation
ExploitIN THE WILD
EPSS (30d)94.30%
PublishedApr 11, 2026

Recommended Actions

  • Apply vendor patches immediately
  • Monitor CVE-2020-3187 in threat intel feeds
  • Review IDS/IPS signatures for exploitation attempts
  • !CISA KEV: Federal agencies must patch per BOD 22-01 timeline
  • !Active exploitation confirmed — treat as P1
Data sourced from NVD (NIST), CISA KEV, and EPSS (FIRST). Analysis generated by CTIWATCH.COM. CVE data is provided under the NVD usage policy.