cbcvebase.
CVE-2020-3580
published 2020-10-21

CVE-2020-3580: Multiple vulnerabilities in the web services interface of Cisco Adaptive Security Appliance (ASA) Software and Cisco Firepower Threat Defense (FTD) Software…

PriorityP184medium6.1CVSS 3.1
AVNACLPRNUIRSCCLILAN
KEVITWEXPLOITRansomware
CISA Known Exploited Vulnerabilitydue 2022-05-03
Exploited in the wild
EPSS
85.44%
99.7th percentile
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.

Affected

11 ranges
VendorProductVersion rangeFixed in
ciscoadaptive_security_appliance
ciscoadaptive_security_appliance_software< 9.8.4.349.8.4.34
ciscoadaptive_security_appliance_software>= 9.10 < 9.12.4.139.12.4.13
ciscoadaptive_security_appliance_software>= 9.13 < 9.13.1.219.13.1.21
ciscoadaptive_security_appliance_software>= 9.14 < 9.14.2.89.14.2.8
ciscoadaptive_security_appliance_software>= 9.15 < 9.15.1.159.15.1.15
ciscoadaptive_security_appliance_software>= 9.9 < 9.9.2.859.9.2.85
ciscocisco_adaptive_security_appliance_software
ciscofirepower_threat_defense< 6.4.0.126.4.0.12
ciscofirepower_threat_defense>= 6.5.0 < 6.6.46.6.4
ciscofirepower_threat_defense>= 6.7.0 < 6.7.0.26.7.0.2

Detection & IOCsextracted from sources · hover to see the quote

url/+CSCOE+/saml/sp/acs?tgname=a
otherSAMLResponse=%22%3E%3Csvg/onload=alert(/{{randstr}}/)%3E
snort
SID 57856
snort
SID 57857
  • The exploit targets the SAML ACS endpoint on Cisco ASA/FTD. Monitor for POST requests to /+CSCOE+/saml/sp/acs with a SAMLResponse parameter containing XSS payloads (e.g., SVG onload handlers or angle-bracket injections).
  • Vulnerability is only exploitable on devices with specific AnyConnect IKEv2 (with client services), AnyConnect SSL VPN, or Clientless SSL VPN (WebVPN) configurations enabled. Audit devices for these configurations as a triage step.
  • CVE-2020-3580 is being actively exploited in the wild following public PoC release by Positive Technologies on June 24, 2021. Treat any unpatched ASA/FTD with WebVPN or AnyConnect exposed to the internet as high priority.
  • HTTP response for a successful XSS probe will return status 200 with Content-Type: text/html and reflect the injected payload in the body. Use this as a detection matcher in web application scanners or proxies.
  • ·The vulnerability only affects devices with AnyConnect IKEv2 Remote Access (with client services), AnyConnect SSL VPN, or Clientless SSL VPN (WebVPN) explicitly enabled. Devices without these configurations are not affected.

CVSS provenance

nvdv3.16.1MEDIUMCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
nvdv2.02.6LOWAV:N/AC:H/Au:N/C:N/I:P/A:N
vulncheck6.1MEDIUM
cisa6.1MEDIUM
vendor_cisco6.1MEDIUM
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