CVE-2020-3187
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…
EPSS Exploitation Probability
EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.
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.
Research use only. For defensive security, authorized penetration testing, and academic research only. Never execute exploit code against systems without explicit written authorization.
Cisco Adaptive Security Appliance Software 9.7 - Unauthenticated Arbitrary File Deletion
by 0xmmnbassel · Jul 29, 2020
Detection & mitigation playbook
VulnerabilityDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for the affected component. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.
Remediation status
No patched version of the affected component has shipped for CVE-2020-3187 yet. Where your build allows, override or pin the dependency away from the vulnerable range, and apply any maintainer-recommended mitigation.
Mitigate without a patch
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 pinpoints whether CVE-2020-3187 is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.
Tailored to CVE-2020-3187. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is CVE-2020-3187 in your dependencies?
O3 detects CVE-2020-3187 across dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.