CVE-2026-20069

Cisco Secure Firewall Adaptive Security Appliance and Secure Firewall Threat Defense Software VPN Web Services Client-Side Request Smuggling Vulnerability

MEDIUM

4.3

CVSS Score

Published: March 4, 2026 at 05:51 PM UTC

Updated: August 11, 2026 at 07:40 PM UTC

2 products affected across 1 vendorAdaptive Security ApplianceSecure Firewall Threat Defense

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Severity

MEDIUM4.3

Exploit prediction

EPSS 0.3%

SSVC

No known exploit

Description

A vulnerability in the VPN web services component of Cisco Secure Firewall Adaptive Security Appliance (ASA) Software and Cisco Secure Firewall Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to conduct browser-based attacks against users of an affected device. This vulnerability is due to improper validation of HTTP requests. An attacker could exploit this vulnerability by persuading a user to visit a website that is designed to pass malicious HTTP requests to a device that is running Cisco Secure Firewall ASA Software or Cisco Secure FTD Software and has web services endpoints supporting VPN features enabled. A successful exploit could allow the attacker to reflect malicious input from the affected device to the browser that is in use and conduct browser-based attacks, including cross-site scripting (XSS) attacks. The attacker is not able to directly impact the affected device.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

Adaptive Security Appliance · Cisco

95%

9.12.1 ≤ v < 9.16.4.859.17.1 ≤ v < 9.18.4.669.19.1 ≤ v < 9.20.49.22.1.1 ≤ v < 9.22.2.49.23.1 ≤ v < 9.23.1.79.12.1 9.12.1.2 9.12.1.3 9.12.2 9.12.2.1 9.12.2.4 9.12.2.5 9.12.2.9 9.12.3 9.12.3.12 9.12.3.2 9.12.3.7 9.12.3.9 9.12.4 9.12.4.10 9.12.4.13 9.12.4.18 9.12.4.2 9.12.4.24 9.12.4.26 9.12.4.29 9.12.4.30 9.12.4.35 9.12.4.37 9.12.4.38 9.12.4.39 9.12.4.4 9.12.4.40 9.12.4.41 9.12.4.47 9.12.4.48 9.12.4.50 9.12.4.52 9.12.4.54 9.12.4.55 9.12.4.56 9.12.4.58 9.12.4.62 9.12.4.65 9.12.4.67 9.12.4.7 9.12.4.8 9.16.1 9.16.1.28 9.16.2 9.16.2.11 9.16.2.13 9.16.2.14 9.16.2.3 9.16.2.7 9.16.3 9.16.3.14 9.16.3.15 9.16.3.19 9.16.3.23 9.16.3.3 9.16.4 9.16.4.14 9.16.4.19 9.16.4.27 9.16.4.38 9.16.4.39 9.16.4.42 9.16.4.48 9.16.4.55 9.16.4.57 9.16.4.61 9.16.4.62 9.16.4.67 9.16.4.70 9.16.4.71 9.16.4.76 9.16.4.82 9.16.4.84 9.16.4.9 9.17.1 9.17.1.10 9.17.1.11 9.17.1.13 9.17.1.15 9.17.1.20 9.17.1.30 9.17.1.33 9.17.1.39 9.17.1.45 9.17.1.46 9.17.1.7 9.17.1.9 9.18.1 9.18.1.3 9.18.2 9.18.2.5 9.18.2.7 9.18.2.8 9.18.3 9.18.3.39 9.18.3.46 9.18.3.53 9.18.3.55 9.18.3.56 9.18.4 9.18.4.22 9.18.4.24 9.18.4.29 9.18.4.34 9.18.4.40 9.18.4.47 9.18.4.5 9.18.4.50 9.18.4.52 9.18.4.53 9.18.4.57 9.18.4.8 9.19.1 9.19.1.12 9.19.1.18 9.19.1.22 9.19.1.24 9.19.1.27 9.19.1.28 9.19.1.31 9.19.1.37 9.19.1.38 9.19.1.42 9.19.1.5 9.19.1.9 9.20.1 9.20.1.5 9.20.2 9.20.2.10 9.20.2.21 9.20.2.22 9.20.3 9.20.3.10 9.20.3.13 9.20.3.16 9.20.3.20 9.20.3.4 9.20.3.7 9.20.3.9 9.20.4 9.22.1.1 9.22.1.2 9.22.1.3 9.22.1.6 9.22.2 9.22.2.4 9.22.2.9 9.23.1 9.23.1.3 9.23.1.7

Affected range stops below 9.16.4.85, so it looks safe — our inference, not a vendor statement

Affected range stops below 9.18.4.66, so it looks safe — our inference, not a vendor statement

Affected range stops below 9.20.4, so it looks safe — our inference, not a vendor statement

Affected range stops below 9.22.2.4, so it looks safe — our inference, not a vendor statement

Affected range stops below 9.23.1.7, so it looks safe — our inference, not a vendor statement

Secure Firewall Threat Defense · Cisco

95%

6.4.0 ≤ v < 7.0.97.1.0 ≤ v < 7.2.117.3.0 ≤ v < 7.4.37.6.0 ≤ v < 7.6.47.7.0 ≤ v < 7.7.116.4.0 6.4.0.1 6.4.0.10 6.4.0.11 6.4.0.12 6.4.0.13 6.4.0.14 6.4.0.15 6.4.0.16 6.4.0.17 6.4.0.18 6.4.0.2 6.4.0.3 6.4.0.4 6.4.0.5 6.4.0.6 6.4.0.7 6.4.0.8 6.4.0.9 7.0.0 7.0.0.1 7.0.1 7.0.1.1 7.0.2 7.0.2.1 7.0.3 7.0.4 7.0.5 7.0.6 7.0.6.1 7.0.6.2 7.0.6.3 7.0.7 7.0.8 7.0.8.1 7.1.0 7.1.0.1 7.1.0.2 7.1.0.3 7.2.0 7.2.0.1 7.2.1 7.2.10 7.2.10.2 7.2.2 7.2.3 7.2.4 7.2.4.1 7.2.5 7.2.5.1 7.2.5.2 7.2.6 7.2.7 7.2.8 7.2.8.1 7.2.9 7.3.0 7.3.1 7.3.1.1 7.3.1.2 7.4.0 7.4.1 7.4.1.1 7.4.2 7.4.2.1 7.4.2.2 7.4.2.3 7.4.2.4 7.6.0 7.6.1 7.6.2 7.6.2.1 7.7.0 7.7.10 7.7.10.1

Affected range stops below 7.0.9, so it looks safe — our inference, not a vendor statement

Affected range stops below 7.2.11, so it looks safe — our inference, not a vendor statement

Affected range stops below 7.4.3, so it looks safe — our inference, not a vendor statement

Affected range stops below 7.6.4, so it looks safe — our inference, not a vendor statement

Affected range stops below 7.7.11, so it looks safe — our inference, not a vendor statement

Remediation

No guide yet

No remediation guidance has been written for this CVE yet. What the record does show:

Patch and advisory references

https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-asaftd-desync-n5AVzEQw

References (1)

Vendor Advisory

Source: cverecord

https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-asaftd-desync-n5AVzEQw

SSVC — Action Prioritization

SSVCNo known exploitNot automatablePartial impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

4.3MEDIUMcisco

Attack Vector: NETWORK
Complexity: LOW
Privileges: NONE
User Interaction: REQUIRED
Scope: UNCHANGED
Confidentiality: NONE
Integrity: LOW
Availability: NONE

Vector?

Quick Info

StatusANALYZED

CWE

CWE-444

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