CVE-2020-3580
Confirmed PUBLISHEDCisco Adaptive Security Appliance Software and Firepower Threat Defense Software Web Services Interface Cross-Site Scripting Vulnerabilities
Recommended Action
Prioritize remediation. Validate affected assets and apply vendor fixes on an accelerated timeline.
At a Glance
Multiple vulnerabilities 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 cross-site scripting (XSS) attacks against a user of the web services interface of an affected device. The vulnerabilities are due to insufficient validation of user-supplied input by the web services interface of an affected device. An attacker could exploit these vulnerabilities by persuading a user of the interface to click a crafted link. A successful exploit could allow the attacker to execute arbitrary script code in the context of the interface or allow the attacker to access sensitive, browser-based information. Note: These vulnerabilities affect only specific AnyConnect and WebVPN configurations. For more information, see the Vulnerable Products section.
- CVE Published
- Oct 21, 2020
- Exploitation Reported
- Nov 03, 2021
- CVSS
- 6.1 Medium
- EPSS
- 85.4%
Affected Versions
| Vendor | Product | Version | Status |
|---|---|---|---|
| Cisco |
Cisco Adaptive Security Appliance (ASA) Software
|
n/a |
Affected |
CVE References
- 20201021 Cisco Adaptive Security Appliance Software and Firepower Threat Defense Software Web Services Interface Cross-Site Scripting Vulnerabilities tools.cisco.com · Vendor Advisory https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory...
Recommended Actions
- Prioritize remediation. Validate affected assets and apply vendor fixes on an accelerated timeline.
- Check enrichment artifacts for scanner coverage and available PoCs before rolling remediation validation.
- Use the Pro API to automate enrichment, telemetry, and workflow delivery for VM, SOC, and CTI pipelines.
Known Exploited Vulnerability Sources
Catalogues that list this CVE as a known exploited vulnerability.
Per-source evidence links for KEV attestations are available through the KEVIntel Pro API.
Learn about Pro API access| Source | Added |
|---|---|
| CISA First | 2021-11-03 00:00 UTC |
| The Shadowserver | 2026-07-08 00:00 UTC |
Scanner Artifacts
Nuclei and Metasploit references linked to this CVE.
| Scanner | Reference | Detected |
|---|---|---|
| Nuclei | https://github.com/projectdiscovery/nuclei-templates/blob/main/http/cves/2020/CVE-2020-3580.yaml | Apr 25, 2025 |
Virtual Patch
Compensating WAF rules to help reduce exposure to this CVE. Rule content and deployable vendor exports are available with KEVIntel Enterprise.
KEVIntel does not currently have a virtual patch for this CVE. When available, KEVIntel virtual patches ship as deployable ModSecurity, Cloudflare, and AWS WAF rules.
Enterprise feature. Virtual patch rule content and deployable vendor exports (ModSecurity, Cloudflare, AWS WAF) are available to KEVIntel Enterprise users.
CVSS Scores
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
AV:N/AC:H/Au:N/C:N/I:P/A:N
Exploitation Status
Exploited in the wild
Recorded 2021-11-03 00:00:00 UTC · CISA
Used in malware
Recorded 2021-11-03 00:00:00 UTC · CISA
Proof of concept available
Recorded 2021-06-25 04:39:30 UTC · GitHub
Weaknesses (CWE)
-
Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
Scanner Integrations
| Scanner | Reference | Detected |
|---|---|---|
| Nuclei | https://github.com/projectdiscovery/nuclei-templates/blob/main/http/cves/2020/CVE-2020-3580.yaml | Apr 25, 2025 |
Potential Proof of Concepts
These PoCs are unverified and could contain malware. Use at your own risk.
github · Created 2022-07-15 00:11:29 UTC · 2 stars
Additional exploits for XSS in Cisco ASA devices discovered by PTSwarm
github · Created 2022-06-24 02:16:05 UTC · 0 stars
Cisco ASA XSS CVE-2020-3580
github · Created 2021-06-28 06:51:26 UTC · 21 stars
Automated bulk IP or domain scanner for CVE 2020 3580. Cisco ASA and FTD XSS hunter.
github · Created 2021-06-25 04:39:30 UTC · 9 stars
nuclei · Created Unknown
Timeline
Key exploitation, disclosure, scanner coverage, and KEV attestation events for this CVE.
-
00:00 UTC 11 days ago00:00 UTC · 11 days ago
KEV confirmed by The Shadowserver
Exploitation attested by an external source
-
00:00 UTC about 1 year ago00:00 UTC · about 1 year ago
Nuclei template available
Scanner coverage available
-
00:00 UTC over 4 years ago00:00 UTC · over 4 years ago
Added to CISA KEV
Listed in the CISA Known Exploited Vulnerabilities catalog
-
00:00 UTC over 4 years ago00:00 UTC · over 4 years ago
First public exploitation report
Exploit observed in malware
-
04:39 UTC about 5 years ago04:39 UTC · about 5 years ago
Public PoC available
Public proof-of-concept code published
-
18:40 UTC over 5 years ago18:40 UTC · over 5 years ago
CVE published
Vulnerability disclosed publicly
-
00:00 UTC over 6 years ago00:00 UTC · over 6 years ago
CVE ID reserved
Identifier reserved by the CNA
Automate This Intelligence with the Pro API
Confidence scoring, exploit status, sensor telemetry, PoCs, scanner integrations, mentions, and tags are available programmatically for VM, SOC, and CTI workflows.
Pro API Example
GET /api/v2/pro/kevs/CVE-2020-3580
{
"cve_id": "CVE-2020-3580",
"title": "Cisco Adaptive Security Appliance Software and Firepower Threat Defense Softw...",
"affected_vendor": "Cisco",
"affected_product": "Cisco Adaptive Security Appliance (ASA) Software",
"affected_versions": [
{ "vendor": "...", "product": "...", "status": "affected", "display_label": "..." }
],
"confidence": "Confirmed",
"cvss_score": 6.1,
"epss_score": 0.85439,
"exploit_status": {
"exploited_in_the_wild": true,
"active_exploitation_observed": false
},
"sensor_telemetry": { "...": "Pro API fields" },
"proof_of_concepts": [ "..." ],
"scanner_integrations": [ "..." ]
}