Adaptive Security Appliance SoftwareOperating system · Cisco

CVE-2024-20299

MEDIUM · 5.8 CVSS v3.1 Published 2024-10-23
Mitigation only
No fix yet — a mitigation exists. There is no fixed release. A documented workaround reduces exposure in the meantime.
See remediation →
67/100
Remediation priority · Elevated
Remotely reachable No privileges Zero-click

Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.

NVD · unedited
A vulnerability in the AnyConnect firewall for Cisco Adaptive Security Appliance (ASA) Software and Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to bypass a configured access control list (ACL) and allow traffic that should have been denied to flow through an affected device. This vulnerability is due to a logic error in populating group ACLs when an AnyConnect client establishes a new session toward an affected device. An attacker could exploit this vulnerability by establishing an AnyConnect connection to the affected device. A successful exploit could allow the attacker to bypass configured ACL rules.

Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.

dbcve analysis · high confidence

A logic error in Cisco ASA and FTD software causes group ACLs to be incorrectly populated when an AnyConnect client establishes a new session, allowing traffic that should be blocked by configured ACLs to flow through the affected device. The vulnerability stems from incorrect handling of group ACL population during AnyConnect session initialization.

MitigationApply Cisco-provided patches for ASA and FTD software when available; in the interim, review and harden edge ACLs and monitor for unexpected traffic patterns that may indicate exploitation.

Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.

Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.

NVD · CPE data
Adaptive Security Appliance SoftwareOperating system
Affected:= 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
Secure Firewall Threat DefenseApplication
Affected:= 6.2.3= 6.2.3.1= 6.2.3.2= 6.2.3.3= 6.2.3.4= 6.2.3.5= 6.2.3.6= 6.2.3.7= 6.2.3.8= 6.2.3.9= 6.2.3.10= 6.2.3.11

CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.

From the vector
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Scope
Changed
Confidentiality
None
Integrity
Low
Availability
None

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:L/A:N

Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.

dbcve checks

Work through these to decide whether this CVE applies to you.

  1. Identify the device type and software
    Run 'show version' or 'show inventory' on the device CLI to determine if it is Cisco ASA or Cisco Firepower Threat Defense (FTD)
    Affected if The device is running Cisco ASA Software or FTD software
  2. Check the installed software version
    Run 'show version' and locate the software version number in the output. Compare it against the affected version lists: ASA versions 9.8.1 through 9.8.2.28 (specific builds: 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) and FTD versions 6.2.3 through 6.2.3.11
    Affected if The installed version matches one of the listed affected versions
  3. Verify AnyConnect is configured
    Run 'show running-config | include anyconnect' or check the VPN configuration to confirm AnyConnect remote access VPN is enabled on the device
    Affected if AnyConnect remote access VPN is configured on the device
  4. Check for group ACL configuration
    Run 'show running-config | include group-policy' and then inspect the group-policy configuration for any access-list (ACL) assignments using 'show running-config group-policy <name>'
    Affected if Group policies with ACLs are configured for VPN users

A device is affected if it runs a matching ASA or FTD version from the affected list AND has AnyConnect VPN configured with group ACLs, as the logic error only manifests during AnyConnect session initialization with group ACLs in use.

Generated from the published advisory. Verify against your own configuration.

Check your environment

Paste your version and any relevant configuration and it will be compared against the affected criteria above. Do not include secrets or credentials.

AI-assisted, checked against the advisory. Informational, not a guarantee.

Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.

From vendor data
Mitigation available No clean upgrade yet — mitigate in the meantime
Mitigation

Apply Cisco-provided patches for ASA and FTD software when available; in the interim, review and harden edge ACLs and monitor for unexpected traffic patterns that may indicate exploitation.

Fix this in Adaptive Security Appliance Software Scoped from the published advisory
  • Consultation4.0 h
  • Implementation8.0 h
  • Testing6.0 h
  • Review / QA4.0 h
22.0 hours of engineering $3,860
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Scan for this in your stack

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References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.

Primary sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2024-20299 in production — separate from our analysis above.

No notes yet

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What this is

A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.

What belongs here
  • Verified mitigations, workarounds, and config changes
  • Version or environment caveats, and links to real fixes
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