Vulnerability report

Exploited in the wild Confirmed confidence In CISA KEV

CVE-2025-20362

Cisco Secure Firewall Adaptive Security Appliance (ASA) Software Denial of Service

Cisco Secure Firewall Adaptive Security Appliance (ASA) Software · 9.8.1

Severity
CVSS 6.5 · Medium
Confidence
Confirmed
Exploit status
Exploited in the wild
EPSS
87.1%
First observed
—
Last observed
—

Decision summary

What security teams need to know first

Direct answers before the deeper technical record.

What it is

CVE-2025-20362 is an unauthenticated vulnerability affecting Cisco Secure Firewall Adaptive Security Appliance (ASA) Software, Cisco Secure Firewall.... Update: On November 5, 2025, Cisco became aware of a new attack...

Is it exploited?

Yes. Previdian tracks this CVE as a known exploited vulnerability. Confidence is confirmed. Listed in CISA KEV. Also confirmed by third-party sources.

Who is affected?

Cisco Secure Firewall Adaptive Security Appliance (ASA) Software 9.8.1.

What should we do?

Prioritize remediation. Validate affected assets and apply vendor fixes on an accelerated timeline.

Overview

Cisco Secure Firewall Adaptive Security Appliance (ASA) Software Denial of Service

Update: 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.

Cisco Affected
Cisco Secure Firewall 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 9.8.2.33 9.8.2.35 9.8.2.38 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 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 9.8.2.45 9.8.4.25 9.8.4.20 9.8.4.22 9.8.4.26 9.8.4.29 9.8.4.32 9.8.4.33 9.8.4.34 9.8.4.35 9.8.4.39 9.8.4.40 9.8.4.41 9.8.4.43 9.8.4.44 9.8.4.45 9.8.4.46 9.8.4.48 9.12.1 9.12.1.2 9.12.1.3 9.12.2 9.12.2.4 9.12.2.5 9.12.2.9 9.12.3 9.12.3.2 9.12.3.7 9.12.4 9.12.3.12 9.12.3.9 9.12.2.1 9.12.4.2 9.12.4.4 9.12.4.7 9.12.4.10 9.12.4.13 9.12.4.8 9.12.4.18 9.12.4.24 9.12.4.26 9.12.4.29 9.12.4.30 9.12.4.35 9.12.4.37 9.12.4.38 9.12.4.39 9.12.4.40 9.12.4.41 9.12.4.47 9.12.4.48 9.12.4.50 9.12.4.52 9.12.4.54 9.12.4.55 9.12.4.56 9.12.4.58 9.12.4.62 9.12.4.65 9.12.4.67 9.14.1 9.14.1.10 9.14.1.6 9.14.1.15 9.14.1.19 9.14.1.30 9.14.2 9.14.2.4 9.14.2.8 9.14.2.13 9.14.2.15 9.14.3 9.14.3.1 9.14.3.9 9.14.3.11 9.14.3.13 9.14.3.18 9.14.3.15 9.14.4 9.14.4.6 9.14.4.7 9.14.4.12 9.14.4.13 9.14.4.14 9.14.4.15 9.14.4.17 9.14.4.22 9.14.4.23 9.14.4.24 9.16.1 9.16.1.28 9.16.2 9.16.2.3 9.16.2.7 9.16.2.11 9.16.2.13 9.16.2.14 9.16.3 9.16.3.3 9.16.3.14 9.16.3.15 9.16.3.19 9.16.3.23 9.16.4 9.16.4.9 9.16.4.14 9.16.4.18 9.16.4.19 9.16.4.27 9.16.4.38 9.16.4.39 9.16.4.42 9.16.4.48 9.16.4.55 9.16.4.57 9.16.4.61 9.16.4.62 9.16.4.67 9.16.4.70 9.16.4.71 9.16.4.76 9.16.4.82 9.16.4.84 9.17.1 9.17.1.7 9.17.1.9 9.17.1.10 9.17.1.11 9.17.1.13 9.17.1.15 9.17.1.20 9.17.1.30 9.17.1.33 9.17.1.39 9.17.1.45 9.17.1.46 9.18.1 9.18.1.3 9.18.2 9.18.2.5 9.18.2.7 9.18.2.8 9.18.3 9.18.3.39 9.18.3.46 9.18.3.53 9.18.3.55 9.18.3.56 9.18.4 9.18.4.5 9.18.4.8 9.18.4.22 9.18.4.24 9.18.4.29 9.18.4.34 9.18.4.40 9.18.4.47 9.18.4.50 9.18.4.52 9.18.4.53 9.18.4.57 9.18.4.66 9.19.1 9.19.1.5 9.19.1.9 9.19.1.12 9.19.1.18 9.19.1.22 9.19.1.24 9.19.1.27 9.19.1.28 9.19.1.31 9.19.1.37 9.19.1.38 9.19.1.42 9.20.1 9.20.1.5 9.20.2 9.20.2.10 9.20.2.21 9.20.2.22 9.20.3 9.20.3.4 9.20.3.7 9.20.3.9 9.20.3.10 9.20.3.13 9.20.3.16 9.20.3.20 9.20.4 9.20.4.7 9.22.1.1 9.22.1.3 9.22.1.2 9.22.1.6 9.22.2 9.22.2.4 9.22.2.9 9.22.2.13 9.23.1 9.23.1.3 9.23.1.7 9.23.1.13
Cisco Affected
Cisco Secure Firewall Threat Defense (FTD) 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 6.2.3.12 6.2.3.13 6.2.3.14 6.2.3.15 6.2.3.16 6.2.3.17 6.2.3.18 6.6.0 6.6.0.1 6.6.1 6.6.3 6.6.4 6.6.5 6.6.5.1 6.6.5.2 6.6.7 6.6.7.1 6.6.7.2 6.4.0 6.4.0.1 6.4.0.3 6.4.0.2 6.4.0.4 6.4.0.5 6.4.0.6 6.4.0.7 6.4.0.8 6.4.0.9 6.4.0.10 6.4.0.11 6.4.0.12 6.4.0.13 6.4.0.14 6.4.0.15 6.4.0.16 6.4.0.17 6.4.0.18 7.0.0 7.0.0.1 7.0.1 7.0.1.1 7.0.2 7.0.2.1 7.0.3 7.0.4 7.0.5 7.0.6 7.0.6.1 7.0.6.2 7.0.6.3 7.0.7 7.0.8 7.1.0 7.1.0.1 7.1.0.2 7.1.0.3 7.2.0 7.2.0.1 7.2.1 7.2.2 7.2.3 7.2.4 7.2.4.1 7.2.5 7.2.5.1 7.2.6 7.2.7 7.2.5.2 7.2.8 7.2.8.1 7.2.9 7.2.10 7.3.0 7.3.1 7.3.1.1 7.3.1.2 7.4.0 7.4.1 7.4.1.1 7.4.2 7.4.2.1 7.4.2.2 7.4.2.3 7.6.0 7.6.1 7.6.2 7.7.0 7.7.10
Published
25 Sep 2025
Exploitation Reported
01 Jun 2026
Attack vector
Remote
Complexity
Low
Privileges
None
User interaction
None

Tags

cisa nuclei_scanner edge

CVE References

  • CVE Record CVE.org · CVE Record https://www.cve.org/CVERecord?id=CVE-2025-20362
  • cisco-sa-asaftd-webvpn-YROOTUW sec.cloudapps.cisco.com · CVE Record https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurity...

Exploitation evidence

Why Previdian marks this CVE as exploited

Third-party attestation and first-party sensor observation are shown separately so teams can judge the evidence chain.

Exploited in the wild

CVE

Recorded 01 Jun 2026

A trusted third party reported exploitation.

Proof of concept available

Nuclei Templates

Recorded 12 Jun 2026

Public scanner or PoC coverage increases practical exploitability.

Known exploited vulnerability sources

Per-source evidence links for KEV attestations are available through the Previdian Pro API.

Learn about Pro API access
Source Added
CVE First 2026-06-01 10:41 UTC
CISA 2026-06-02 14:06 UTC
The Shadowserver 2026-06-27 10:15 UTC

Detection

Operational artifacts and observed signals

Make the evidence actionable in scanner, SOC, and edge-control workflows.

Observed signals

Request targets
User-Agents
Callback hosts
0
0
0

Request targets and User-Agents available in Pro. Callback host details available in Enterprise.

Virtual patch status

No Previdian virtual patch is currently available. Future rules ship for ModSecurity, Cloudflare, and AWS WAF.

Learn about virtual patches →

Scanner Artifacts

Scanner and exploit-framework references linked to this CVE.

Risk and context

Severity, weaknesses, and research context

CVSS v3.1

6.5 Medium

Potential damage if exploited. Separate from whether attackers are using it.

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

EPSS

87.1%

Estimated chance of exploitation in the next 30 days. Previdian's warning comes from evidence, not this score.

Potential Proof of Concepts

These PoCs are unverified and could contain malware. Use at your own risk.

Timeline

From disclosure to observed exploitation

  1. 10:15 UTC

    KEV confirmed by The Shadowserver

    Exploitation attested by an external source

  2. 14:21 UTC

    Public PoC available

    Public proof-of-concept code published

  3. 14:06 UTC

    Added to CISA KEV

    Listed in the CISA Known Exploited Vulnerabilities catalog

  4. 15:34 UTC

    Nuclei template available

    Scanner coverage available

  5. 10:41 UTC

    Added to Previdian KEV Feed

    High-confidence, third-party attested exploitation

  6. 16:12 UTC

    CVE published

    Vulnerability disclosed publicly

  7. 19:15 UTC

    CVE ID reserved

    Identifier reserved by the CNA

Pro API

Automate this intelligence

Confidence, exploit status, sensor telemetry, PoCs, scanner integrations, mentions, and tags are available programmatically for VM, SOC, and CTI workflows.

  • Evidence confidence and provenance
  • First-party sensor telemetry
  • PoC and scanner references
  • Affected versions and enrichment
  • Automation-ready JSON delivery

GET /api/v2/pro/kevs/CVE-2025-20362

Free JSON includes basic KEV fields
{
  "cve_id": "CVE-2025-20362",
  "confidence": "Confirmed",
  "cvss_score": 6.5,
  "cvss_estimated": false,
  "epss_score": 0.87085,
  "exploit_status": {
    "exploited_in_the_wild": true,
    "active_exploitation_observed": false
  },
  "sensor_telemetry": { "attempts": 0, "sensors": 0 }
}