CVE-2020-3259: Cisco ASA and FTD Information Disclosure Vulnerability
Advisory generated from the CVE record, CISA, Exploit Observer and VEDAS: what it is, whether it is exploited, who is affected, and how to fix and detect it.
Generated by VEDAS. Scores as of 2026-11-08 00:03 UTC. Rebuilt every few hours from cve-scores, CISA KEV and vedas-signatures. How this works and its limits.
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 retrieve memory contents on an affected device, which could lead to the disclosure of confidential information. The vulnerability is due to a buffer tracking issue when the software parses invalid URLs that are requested from the web services interface. An attacker could exploit this vulnerability by sending a crafted GET request to the web services interface. A successful exploit could allow the attacker to retrieve memory contents, which could lead to the disclosure of confidential information. Note: This vulnerability affects only specific AnyConnect and WebVPN configurations. For more information, see the Vulnerable Products section.
Description quoted from the CVE record (assigned by cisco, published 2020-05-06).
Weakness: CWE-200
How it can be exploited
Exploitable over the network with low attack complexity needing no privileges and no user interaction. Impact: confidentiality high, integrity none, availability none. CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
CISA assessment (SSVC): CISA assesses exploitation as active. Automatable: yes. Technical impact: partial.
- On CISA KEV since
- 2024-02-15
- US federal deadline
- 2024-03-07
- Ransomware use
- Yes
Public exploit evidence (Exploit Observer)
Exploit Observer found 1 research write-up naming this CVE.
See all 8 references on Exploit Observer
Live scores
- EPSS
- 0.715
very likely to be attacked soon - VEDAS
- 0.978
strong exploit evidence - On CISA KEV
- Yes, since 2024-02-15
- Detection rule
- No public rule yet
Thin horizontal line: the “likely exploited” threshold (EPSS 0.10, VEDAS 0.5). Shaded “no data” areas are periods when cve-scores did not publish.
Who is affected
| Product | Affected | Not affected |
|---|---|---|
| Cisco Adaptive Security Appliance (ASA) Software | versions not stated in the record | Not stated |
Version ranges exactly as the CVE record states them. “Before X” means X is the first fixed version.
How to fix it
CISA required action: Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable.
Vendor guidance:
- 20200506 Cisco Adaptive Security Appliance Software and Firepower Threat Defense Software Web Services Information Disclosure Vulnerability (vendor-advisory, x_refsource_CISCO)
How to detect it
There is no open VEDAS detection rule for this bug yet. It is listed on the detection gaps page if CISA has confirmed attacks.
Advisories on this CVE
- CISA, FBI and partners warn SafePay ransomware has hit at least 600 critical-infrastructure victims (full advisory)
References
Vendor advisories and patches
- 20200506 Cisco Adaptive Security Appliance Software and Firepower Threat Defense Software Web Services Information Disclosure Vulnerability (vendor-advisory, x_refsource_CISCO)
Government sources
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2020-3259 (government-resource)
Other databases
Where this comes from
This advisory is generated automatically by VEDAS from: CVE.org record, CISA KEV, cve-scores (EPSS and VEDAS), Exploit Observer. Text in quotes is reproduced from the source; everything else is a fixed template filled with source fields. Nothing here is written by a language model. Check the vendor advisory before acting, and read how VEDAS and Exploit Observer work, and their limits.
Supporting partners
