Adaptive Security Appliance SoftwareOperating system · Cisco
CVE-2025-20362
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 · uneditedUpdate: On November 5, 2025, Cisco became aware of a new attack variant against devices running Cisco Secure ASA Software or Cisco Secure FTD Software releases that are affected by CVE-2025-20333 and CVE-2025-20362. This attack can cause unpatched devices to unexpectedly reload, leading to denial of service (DoS) conditions. Cisco strongly recommends that all customers upgrade to the fixed software releases that are listed in the Fixed Software ["#fs"] section of this advisory. A vulnerability in the VPN web server of Cisco Secure Firewall Adaptive Security Appliance (ASA) Software and Cisco Secure Firewall Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to access restricted URL endpoints that are related to remote access VPN that should otherwise be inaccessible without authentication. This vulnerability is due to improper validation of user-supplied input in HTTP(S) requests. An attacker could exploit this vulnerability by sending crafted HTTP requests to a targeted web server on a device. A successful exploit could allow the attacker to access a restricted URL without authentication.
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 confidenceCVE-2025-20362 is an authentication bypass vulnerability in the VPN web server of Cisco Secure Firewall ASA and FTD software. The flaw stems from improper validation of user-supplied input in HTTP(S) requests, allowing unauthenticated remote attackers to access restricted URL endpoints related to remote access VPN that should require authentication. This enables unauthorized access to VPN-related web resources without valid credentials.
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
>= 9.12, < 9.12.4.72>= 9.14, < 9.14.4.28>= 9.16, < 9.16.4.85>= 9.17.0, < 9.18.4.67>= 9.19, < 9.20.4.10>= 9.22, < 9.22.2.14>= 9.23, < 9.23.1.19
Secure Firewall Threat DefenseApplication
>= 7.0.0, < 7.0.8.1>= 7.1.0, < 7.2.10.2>= 7.3.0, < 7.4.2.4>= 7.6.0, < 7.6.2.1>= 7.7.0, < 7.7.10.1CVSS 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
- Unchanged
- Confidentiality
- Low
- Integrity
- Low
- Availability
- High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:H
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 checksWork through these to decide whether this CVE applies to you.
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Determine installed ASA software versionRun `show version` on the ASA CLI and locate the 'Software Version' line in the outputAffected if The version falls within any of these ranges: >= 9.12 but < 9.12.4.72; >= 9.14 but < 9.14.4.28; >= 9.16 but < 9.16.4.85; >= 9.17 but < 9.18.4.67; >= 9.19 but < 9.20.4.10; >= 9.22 but < 9.22.2.14; >= 9.23 but < 9.23.1.19
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Determine installed FTD software versionRun `show version` or `system version` on the FTD CLI and locate the version stringAffected if The version falls within any of these ranges: >= 7.0.0 but < 7.0.8.1; >= 7.1.0 but < 7.2.10.2; >= 7.3.0 but < 7.4.2.4; >= 7.6.0 but < 7.6.2.1; >= 7.7.0 but < 7.7.10.1
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Audit VPN web server access logs for authentication bypassReview `show logging | include +CSCOE+` or examine external authentication logs for requests to VPN-related URLs that occur without corresponding successful authentication eventsAffected if HTTP requests to restricted VPN endpoints (such as /+CSCOE+/ or /webvpn/) appear in logs without preceding successful authentication
A device is affected if it runs a Cisco ASA or FTD version within the listed ranges AND has remote access VPN with the web server interface enabled and accessible.
Generated from the published advisory. Verify against your own configuration.
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.
dbcve · scoped7.0.8.17.2.10.27.4.2.4
Upgrade to the fixed software releases listed in Cisco's advisory. There is also a related DoS attack variant (CVE-2025-20333) that can cause unpatched devices to reload, further emphasizing the urgency of patching.
ASA: 9.12.4.72 / 9.14.4.28 / 9.16.4.85 / 9.18.4.67 (depending on branch); FTD: 7.0.8.1 / 7.2.10.2 / 7.4.2.4 / 7.6.2.1 (depending on branch)
- Identify the current Cisco ASA or FTD software version by running 'show version' on the device CLI
- Determine which version branch your current release belongs to (9.12.x, 9.14.x, 9.16.x, 9.17.x/9.18.x for ASA; or 7.0.x, 7.1.x, 7.3.x, 7.6.x for FTD)
- Download the appropriate fixed software release from Cisco for your version branch (ASA: 9.12.4.72, 9.14.4.28, 9.16.4.85, or 9.18.4.67; FTD: 7.0.8.1, 7.2.10.2, 7.4.2.4, or 7.6.2.1)
- Upload the new software image to the device using the device CLI or management interface
- Perform the upgrade using the 'install' command or relevant upgrade procedure for your platform
- After upgrade completes, verify the new version is running with 'show version'
- Confirm the restricted VPN URLs now require proper authentication
Generated from the published advisory — verify against the referenced sources before acting.
Fix this in Adaptive Security Appliance Software
Exploited in the wild — priority engagement
- Consultation4.0 h
- Implementation6.0 h
- Testing4.0 h
- Review / QA2.0 h
An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $4,544.
Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2025-20362 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.
References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.
Primary sourcesPractitioner notes
ContributedPeer-ranked notes from engineers who’ve handled CVE-2025-20362 in production — separate from our analysis above.
The advisory tells you what broke. It rarely tells you what actually worked. If you’ve dealt with this one, that detail is what the next engineer is searching for.
- The version that genuinely resolved it — not the one the vendor claimed
- A config change or rule that shut the vector down
- A gotcha in the upgrade path that cost you an afternoon
No notes yet
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