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Vulnerabilities/CVE-2023-20269Public Intelligence Dossier
Source: cisco · Limited verification•Last verified: •Collection Degraded
CVE-2023-20269ListedCRITICAL (raw)CVSS 9.1CWE-288

A vulnerability in the remote access VPN feature of Cisco Adaptive Security Appliance (ASA) Software and Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to conduct a brute force attack in an attempt to identify valid username and password combinations or an authenticated, remote attacker to establish a clientless SSL VPN session with an unauthorized user

Published: 06 Sept 2023•Last updated: 12 Aug 2026, 01:03 AM IST•Source identifier: psirt@cisco.com
Dossier completeness: source-provided sections 3 / 3 · rule guidance available. Missing source facts count as incomplete.
Official source
CISA KEV catalog
Listed
Added13 Sept 2023
Due04 Oct 2023
RansomwareKnown
CVSS score
9.1CRITICAL (raw)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
Metric sourcenvd@nist.gov
EPSS probability
26.6%0.266
Percentile98th
Weakness type
CWE-288
CWE-863
Remediation
Patch status unknown
No fixed version or KB recorded

Why It Matters

Analysis dossier

Why It Matters

A vulnerability in the remote access VPN feature of Cisco Adaptive Security Appliance (ASA) Software and Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to conduct a brute force attack in an attempt to identify valid username and password combinations or an authenticated, remote attacker to establish a clientless SSL VPN session with an unauthorized user. This vulnerability is due to improper separation of authentication, authorization, and accounting (AAA) between the remote access VPN feature and the HTTPS management and site-to-site VPN features. An attacker could exploit this vulnerability by specifying a default connection profile/tunnel group while conducting a brute force attack or while establishing a clientless SSL VPN session using valid credentials. A successful exploit could allow the attacker to achieve one or both of the following: Identify valid credentials that could then be used to establish an unauthorized remote access VPN session. Establish a clientless SSL VPN session (only when running Cisco ASA Software Release 9.16 or earlier). Notes: Establishing a client-based remote access VPN tunnel is not possible as these default connection profiles/tunnel groups do not and cannot have an IP address pool configured. This vulnerability does not allow an attacker to bypass authentication. To successfully establish a remote access VPN session, valid credentials are required, including a valid second factor if multi-factor authentication (MFA) is configured. Cisco will release software updates that address this vulnerability. There are workarounds that address this vulnerability.

SOC priority

Immediate Attention

Actively exploited (source statement)

Yes

Publicly disclosed

Unknown

Risk basis: CISA KEV exploitation signal; SOC ecosystem technology relevance; CRITICAL severity; Source-confirmed exploitation or CISA KEV/ransomware metadata

Affected Products & Remediation

1 source-backed product
Affected products and versions (source)
  • cisco adaptive security appliance software · 9.8.1; 9.8.1.5; 9.8.1.7; 9.8.2; 9.8.2.8; 9.8.2.14; 9.8.2.15; 9.8.2.17; 9.8.2.20; 9.8.2.24; 9.8.2.26; 9.8.2.28; 9.8.2.33; 9.8.2.35; 9.8.2.38; 9.8.3; 9.8.3.8; 9.8.3.11; 9.8.3.14; 9.8.3.16; 9.8.3.18; 9.8.3.21; 9.8.3.26; 9.8.3.29; 9.8.4; 9.8.4.3; 9.8.4.7; 9.8.4.8; 9.8.4.10; 9.8.4.12; 9.8.4.15; 9.8.4.17; 9.8.4.20; 9.8.4.22; 9.8.4.25; 9.8.4.26; 9.8.4.29; 9.8.4.32; 9.8.4.33; 9.8.4.34 · NVD CPE · Source
Recorded patch / KBNot provided by source

Vendor or catalog guidance (source)

  • CISA KEV: Apply mitigations per vendor instructions for group-lock and vpn-simultaneous-logins or discontinue use of the product for unsupported devices.

Known exploitation (source facts)

Only what a source states. Unknown means no source has said either way; it is not "not exploited".

CISA KEV
Listed
Exploited (source statement)
Yes
Publicly disclosed (source)
Unknown

CISA required action: Apply mitigations per vendor instructions for group-lock and vpn-simultaneous-logins or discontinue use of the product for unsupported devices.

Suggested hunting (rule-based inference)

SecOps Signal recommendation (rule-based inference). These steps are hunting hypotheses from the vulnerability class; they do not state or imply that exploitation occurred here or anywhere.

Matched kev-network-exposure (CVSS AV:N, CISA KEV Listed); edge-auth-bypass (CWE-863, Affected product: cisco secure firewall threat defense)

Exposure

  1. Identify assets with the exact CVE and confirm the affected product/version against the advisory.Telemetry: DeviceTvmSoftwareVulnerabilities · KEV listing raises urgency, but inventory is needed to establish local exposure. · Rule kev-network-exposure
  2. Identify affected edge devices and verify product versions using device inventory.Telemetry: CommonSecurityLog · The device must match the advisory before exposure is assumed. · Rule edge-auth-bypass

Exploitation evidence

  1. Review relevant edge or application access logs for unusual requests around the advisory window.Telemetry: CommonSecurityLog · Log review is a hunting hypothesis; KEV listing alone does not show local exploitation. · Rule kev-network-exposure
Show more (2)

Exploitation evidence

  1. Review authentication and administrative access events for unexpected successful sessions.Telemetry: CommonSecurityLog · An authentication weakness warrants targeted access-log review. · Rule edge-auth-bypass

Response

  1. Recheck the affected assets after the source-stated mitigation or update is applied.Telemetry: DeviceTvmSoftwareVulnerabilities · A follow-up inventory check verifies local remediation. · Rule kev-network-exposure

CISA KEV Record

Catalog entry
13 Sept 2023
Required action due
04 Oct 2023
Known ransomware use
Known

Apply mitigations per vendor instructions for group-lock and vpn-simultaneous-logins or discontinue use of the product for unsupported devices.

Change History & Source Data

— No recorded material change

CNA / source
psirt@cisco.com
Record status · verification
UPDATED · CISA KEV confirmed
CPE
cpe:2.3:o:cisco:adaptive_security_appliance_software:9.8.1:*:*:*:*:*:*:*, cpe:2.3:o:cisco:adaptive_security_appliance_software:9.8.1.5:*:*:*:*:*:*:*, cpe:2.3:o:cisco:adaptive_security_appliance_software:9.8.1.7:*:*:*:*:*:*:*, cpe:2.3:o:cisco:adaptive_security_appliance_software:9.8.2:*:*:*:*:*:*:*, cpe:2.3:o:cisco:adaptive_security_appliance_software:9.8.2.8:*:*:*:*:*:*:*, cpe:2.3:o:cisco:adaptive_security_appliance_software:9.8.2.14:*:*:*:*:*:*:*, cpe:2.3:o:cisco:adaptive_security_appliance_software:9.8.2.15:*:*:*:*:*:*:*, cpe:2.3:o:cisco:adaptive_security_appliance_software:9.8.2.17:*:*:*:*:*:*:*, cpe:2.3:o:cisco:adaptive_security_appliance_software:9.8.2.20:*:*:*:*:*:*:*, cpe:2.3:o:cisco:adaptive_security_appliance_software:9.8.2.24:*:*:*:*:*:*:*

Evidence & Provenance

4 public sources
CISA KEV CatalogAdded 2023-09-13sec.cloudapps.cisco.comSource recordnvd.nist.govSource recordcisa.govSource record

Linked by the query's stored exact CVE association. Review required tables and validation status before use.

Detection Hunting Query
Target: DeviceTvmSoftwareVulnerabilities•Defender XDR
Detect endpoints exposed to CVE-2023-20269
Purpose: Exposure assessment (Category: Exposure Check)Why linked: Query metadata names CVE-2023-20269
DeviceTvmSoftwareVulnerabilities| where CveId == "CVE-2023-20269"| project DeviceId, DeviceName, OSPlatform, OSVersion, SoftwareVendor, SoftwareName, SoftwareVersion, CveId, VulnerabilitySeverityLevel, RecommendedSecurityUpdate, RecommendedSecurityUpdateId| sort by VulnerabilitySeverityLevel desc
Schema Checked · Not runtime validatedSource: SecOps Signal deterministic template · Limited verificationStatic screening: Passed structure and schema checks; tenant execution is not verified.
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Correlated briefings

SecOps Signal surfaces public advisory facts only. A missing value means the source has not published it, not that your environment is unaffected. No tenant inventory is connected.