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CVE-2023-20269

Cisco — Cisco Adaptive Security Appliance and Firepower Threat Defense Unauthorized Access Vulnerability

Cisco · CWE-288 | CWE-863 — Incorrect authorization · in CISA KEV since 2023-09-13

ExigentKEV since 2023 · listed over a yearRansomwareCISA KEVActively Exploited
85

EVRS 85 of 100 Immediate

Out-of-Band / Urgent Remediation

Rank 436 of 2,962 tracked

Raised to the floor for a confirmed exploited vulnerability.

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Why it scores 85

Evidence available: 6 of 7 signals

Listed in the CISA KEV catalog, and associated with known ransomware campaigns.

  • CISA KEVApplied
  • RansomwareApplied
  • Vendor exploitationDid not apply
  • EPSSApplied
  • Microsoft Exploitability IndexNot applicable
  • Pre-patch disclosureNo data
  • KEV recencyDid not apply
  • CVSSApplied

The band answers “how soon”, not “how bad”. No data for: Pre-patch disclosure. Why some signals show no data

Fix

No fixed version identified yet

CISA required action

Affected versions

  • secure firewall threat defense6.2.36.2.3.16.2.3.26.2.3.36.2.3.46.2.3.56.2.3.66.2.3.76.2.3.86.2.3.96.2.3.106.2.3.116.2.3.126.2.3.136.2.3.146.2.3.156.2.3.166.2.3.176.2.3.186.4.06.4.0.16.4.0.26.4.0.36.4.0.46.4.0.56.4.0.66.4.0.76.4.0.86.4.0.96.4.0.106.4.0.116.4.0.126.4.0.136.4.0.146.4.0.156.4.0.166.6.06.6.0.16.6.16.6.36.6.46.6.56.6.5.16.6.5.26.6.76.6.7.16.7.06.7.0.16.7.0.26.7.0.37.0.07.0.0.17.0.17.0.1.17.0.27.0.2.17.0.37.0.47.0.57.0.67.1.07.1.0.17.1.0.27.1.0.37.2.07.2.0.17.2.17.2.27.2.37.2.47.2.4.17.2.57.3.07.3.17.3.1.17.4.0
  • adaptive security appliance software9.8.19.8.1.59.8.1.79.8.29.8.2.89.8.2.149.8.2.159.8.2.179.8.2.209.8.2.249.8.2.269.8.2.289.8.2.339.8.2.359.8.2.389.8.39.8.3.89.8.3.119.8.3.149.8.3.169.8.3.189.8.3.219.8.3.269.8.3.299.8.49.8.4.39.8.4.79.8.4.89.8.4.109.8.4.129.8.4.159.8.4.179.8.4.209.8.4.229.8.4.259.8.4.269.8.4.299.8.4.329.8.4.339.8.4.349.8.4.359.8.4.399.8.4.409.8.4.419.8.4.439.8.4.449.8.4.459.8.4.469.8.4.489.12.19.12.1.29.12.1.39.12.29.12.2.19.12.2.49.12.2.59.12.2.99.12.39.12.3.29.12.3.79.12.3.99.12.3.129.12.49.12.4.29.12.4.49.12.4.79.12.4.89.12.4.109.12.4.139.12.4.189.12.4.249.12.4.269.12.4.299.12.4.309.12.4.359.12.4.379.12.4.389.12.4.399.12.4.409.12.4.419.12.4.479.12.4.489.12.4.509.12.4.529.12.4.549.12.4.559.12.4.569.12.4.589.14.19.14.1.69.14.1.109.14.1.159.14.1.199.14.1.309.14.29.14.2.49.14.2.89.14.2.139.14.2.159.14.39.14.3.19.14.3.99.14.3.119.14.3.139.14.3.159.14.3.189.14.49.14.4.69.14.4.79.14.4.129.14.4.139.14.4.149.14.4.159.14.4.179.14.4.229.14.4.239.15.19.15.1.19.15.1.79.15.1.109.15.1.159.15.1.169.15.1.179.15.1.219.16.19.16.1.289.16.29.16.2.39.16.2.79.16.2.119.16.2.139.16.2.149.16.39.16.3.39.16.3.149.16.3.159.16.3.199.16.3.239.16.49.16.4.99.16.4.149.16.4.189.16.4.199.16.4.279.16.4.389.17.19.17.1.79.17.1.99.17.1.109.17.1.119.17.1.139.17.1.159.17.1.209.17.1.309.18.19.18.1.39.18.29.18.2.59.18.2.79.18.2.89.18.39.18.3.399.18.3.469.18.3.539.18.3.559.19.19.19.1.59.19.1.99.19.1.129.19.1.18

Remediation

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

Evidence

Each value with its source
MeasureValueSource
CVSS base scoreHow severe the flaw is in itself. It does not say how likely an attack is. 9.1 NVD
FIRST EPSSFIRST's estimate of the chance this is exploited in the next 30 days, and how that ranks against all CVEs. 0.255 (97.9th pctl) FIRST EPSS
Actively exploitedWhether a source of record has confirmed attacks using it in the wild. Confirmed CISA KEV
Ransomware campaign useWhether CISA has seen ransomware operators use it. Known CISA KEV
CISA remediation deadlineThe date US federal agencies must have fixed or mitigated it. 2023-10-04 · KEV since 2023 · listed over a year CISA KEV
Public exploit moduleA module existing is not the same as active exploitation. None known Metasploit
EUVD cross-referenceENISA's record: CVSS 5.0 (v3.1), assigned by cisco. Listed ENISA EUVD

Description

NVD

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.

What CISA says to do