A vulnerability in the remote access VPN feature of Cisco Adaptive Security Appliance (ASA) Software and Cisco Firepower Threat Defense (FTD
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.
- Published
- Sep 6, 2023
- Updated
- Aug 11, 2026
- EPSS
- 25.5% · 98th percentile
- CWE
- CWE-288
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Report tools
Action score
74
This week
Don’t wait for the next maintenance window.
- CVSS
- 36 / 40 · 9.1 / 10
- CISA KEV
- 30 / 30 · Listed
- EPSS
- 8 / 30 · 25.5%
CISA SSVC decision
- Exploitation
- active
- Automatable
- no
- Technical impact
- partial
Vulnrichment: CISA's decision-tree inputs.
CNA vs NVD score
- NVD
- 9.1
- CNA · cisco
- 5.0
- 4.1 point gap
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:N/I:L/A:N
The score given by the assigning authority versus NVD’s independent score. A gap means the severity is contested.
Actively exploited in the wild
CISA added this to its Known Exploited Vulnerabilities catalog on Sep 13, 2023. That signals real attacks, not theory.
Remediation deadline for government agencies: Oct 4, 2023.
Known to be used in ransomware campaigns.
Affected systems
| Vendor | Product | CPE |
|---|---|---|
| cisco | adaptive security appliance software | cpe:2.3:o:cisco:adaptive_security_appliance_software |
| cisco | secure firewall threat defense | cpe:2.3:a:cisco:secure_firewall_threat_defense |
Using adaptive security appliance software? Add it to your stack and be the first to know about CVEs like this one. (Firewall)
Affected versions
NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.
- cisco adaptive security appliance software9.12.1
- cisco adaptive security appliance software9.12.1.2
- cisco adaptive security appliance software9.12.1.3
- cisco adaptive security appliance software9.12.2
- cisco adaptive security appliance software9.12.2.1
- cisco adaptive security appliance software9.12.2.4
- cisco adaptive security appliance software9.12.2.5
- cisco adaptive security appliance software9.12.2.9
- cisco adaptive security appliance software9.12.3
- cisco adaptive security appliance software9.12.3.12
- cisco adaptive security appliance software9.12.3.2
- cisco adaptive security appliance software9.12.3.7
- cisco adaptive security appliance software9.12.3.9
- cisco adaptive security appliance software9.12.4
- cisco adaptive security appliance software9.12.4.10
- cisco adaptive security appliance software9.12.4.13
- cisco adaptive security appliance software9.12.4.18
- cisco adaptive security appliance software9.12.4.2
- cisco adaptive security appliance software9.12.4.24
- cisco adaptive security appliance software9.12.4.26
Versions reported by the vendor
Affected version ranges reported by the assigning authority (cisco). Independent of NVD's CPE analysis and usually ahead of it.
Cisco Cisco Adaptive Security Appliance (ASA) 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 … (+28)affected
Cisco Cisco Firepower Threat Defense Software
- 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, 6.2.3.10, 6.2.3.11, 6.2.3.9 … (+28)affected
Same product
cisco: all recordsOther highest-scoring records for the same primary product.
- CVE-2025-20362Update: On November 5, 2025, Cisco became aware of a new attack variant against devices running Cisco Secure ASA Software or Cisco Secure FTKEV90Now
- CVE-2025-20333A vulnerability in the VPN web server of Cisco Secure Firewall Adaptive Security Appliance (ASA) Software and Cisco Secure Firewall Threat DKEV90Now
- CVE-2020-3452Cisco Adaptive Security Appliance Software and Firepower Threat Defense Software Web Services Read-Only Path Traversal VulnerabilityKEV90Now
- CVE-2018-0296A vulnerability in the web interface of the Cisco Adaptive Security Appliance (ASA) could allow an unauthenticated, remote attacker to causeKEV90Now
- CVE-2024-20353A vulnerability in the management and VPN web servers for Cisco Adaptive Security Appliance (ASA) Software and Cisco Firepower Threat DefensKEV85Now
- CVE-2016-6367Cisco Adaptive Security Appliance (ASA) Software before 8.4(1) on ASA 5500, ASA 5500-X, PIX, and FWSM devices allows local users to gain priKEV68This week
Remediation
Which version to upgrade to
Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.
No fix version is recorded for this entry. Check the references for vendor advisories.
Exploit status
Weaponized
A ready exploit tool or active in-the-wild use is known for this vulnerability. This should be your top priority.
Research context
For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.
Timeline
From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.
- Published
- CISA KEV+6 d
- TodaySep 29, 2026+1119 d
FIRST EPSS daily score; only changes of 0.01 or more are recorded (step chart).
Patch and commit links
Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.
No commit or PR link among the references.
Credits
All researchersFinders, reporters and analysts named in the CNA record. Click a name for that researcher’s other records.
No credits in the CNA record.
Variant candidates
Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.
No nightly-computed relations.
Chain candidates
An authentication bypass and a privilege-requiring bug in the same product, published close together: combined they may become an unauthenticated path.
—
Bug bounty scope
No known public program.
Source: bounty-targets-data (public HackerOne, Bugcrowd, Intigriti, YesWeHack listings).
Technical details
Attack conditions
- Anyone who can reach it over the internet can trigger it.
- No account or password is required.
- No user action is required.
- No special conditions are required; it is repeatable.
If successful
- Confidentiality
- high · data can be read
- Integrity
- high · data or configuration can be modified
- Availability
- none
- Attack vector
- Network
- Attack complexity
- Low
- Privileges required
- None
- User interaction
- None
- Scope
- Unchanged
- Confidentiality impact
- High
- Integrity impact
- High
- Availability impact
- None
Weakness class (CWE)
CWE-288 · Authentication Bypass Using an Alternate Path or ChannelCVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
nvd-primary
Attack context
MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.
Attack patterns (CAPEC)
Noroxi analysis
No Noroxi analysis for this record yet
We don't hand-write analysis for all 385,000+ vulnerabilities; that wouldn't be honest. For notable, high-impact vulnerabilities our team writes the mechanism, detection and remediation steps.
We use this product, ask for helpChange log
No changes recorded on tracked fields yet. Score, KEV, exploit maturity and fix status changes appear here.
References
- sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-asaftd-ravpn-auth-8LyfCkeC
- www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2023-20269
Vendor advisories and official records. Exploit/PoC links are deliberately left out.