Cyber Resilience

CVE-2025-20362

Access Control in Cisco Adaptive Security Appliance Software 9.12 – 9.12.4.72

CISA KEVActive ExploitationEUVD ExploitedAccess Control
Published
25 September 2025
Modified
11 August 2026
KEV Added
25 September 2025
Patch / advisory
CVSS Score v3.1 6.5
Click a component to see what it means
Raw vectorCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N
EPSS Score 0.87 99.7th percentile
Risk Priority 77 floored blend · peak EPSS

Summary

CVE-2025-20362 is a medium-severity Missing Authorization (CWE-862) vulnerability in Cisco Adaptive Security Appliance Software. Its CVSS base score is 6.5 (Medium).

Operationally, exploitation aligns with the MITRE ATT&CK technique Exploitation for Privilege Escalation (T1068); ranked in the top 0.3% of CVEs by exploit likelihood; CISA has added it to the Known Exploited Vulnerabilities catalog.

The strongest mitigations our analysis identified map to AC-24 (Access Control Decisions) and AC-25 (Reference Monitor) — see the control section below for these in your framework.

Deeper analysis AI-assisted summary

Synthesised by an AI model from the NVD description and linked references — a reading aid, not an authoritative source.

A vulnerability in the VPN web server of Cisco Secure Firewall Adaptive Security Appliance (ASA) Software and Cisco Secure Firewall Threat Defense (FTD) Software stems from improper validation of user-supplied input in HTTP(S) requests. The flaw, tracked as CVE-2025-20362 with CWE-862, enables access to restricted remote-access VPN URL endpoints that should require authentication. It affects devices running releases also covered by the related CVE-2025-20333.

An unauthenticated remote attacker can exploit the issue by sending crafted HTTP requests to the device's web server, gaining access to otherwise protected VPN-related endpoints. A later attack variant observed in November 2025 can additionally trigger unexpected reloads on unpatched devices, producing denial-of-service conditions.

Cisco's advisory directs customers to apply the fixed software releases listed in the advisory and strongly recommends upgrading all affected ASA and FTD installations. The vulnerability appears in the CISA Known Exploited Vulnerabilities catalog.

EPSS for the CVE reached a peak of 0.5700 on 2026-04-26 before receding to the current value of 0.4350, indicating elevated exploitation interest after disclosure.

OWASP Top 10 for Web (2025)

EU & UK References

Vulnerability Data

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…

more

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.

CWE(s)
KEV Date Added
25 September 2025

Related Threats

MITRE ATT&CK Enterprise Techniques

T1068 Exploitation for Privilege Escalation Privilege Escalation
Adversaries may exploit software vulnerabilities in an attempt to elevate privileges.
T1190 Exploit Public-Facing Application Initial Access
Adversaries may attempt to exploit a weakness in an Internet-facing host or system to initially access a network.
T1210 Exploitation of Remote Services Lateral Movement
Adversaries may exploit remote services to gain unauthorized access to internal systems once inside of a network.
T1548 Abuse Elevation Control Mechanism Privilege Escalation
Adversaries may circumvent mechanisms designed to control privilege elevation to gain higher-level permissions.
T1556 Modify Authentication Process Defense Impairment
Adversaries may modify authentication mechanisms and processes to access user credentials or enable otherwise unwarranted access to accounts.
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2024-20355Same product: Cisco Adaptive Security Appliance Software
CVE-2023-20064Same vendor: Cisco
CVE-2024-20442Same vendor: Cisco
CVE-2024-20477Same vendor: Cisco
CVE-2025-20301Same vendor: Cisco
CVE-2025-20302Same vendor: Cisco
CVE-2021-30657Shared CWE-862both on KEV
CVE-2021-37976Shared CWE-862both on KEV
CVE-2024-57726Shared CWE-862both on KEV
CVE-2021-30713Shared CWE-862both on KEV

Affected Assets

cisco
adaptive security appliance software
9.12 — 9.12.4.72 · 9.14 — 9.14.4.28 · 9.16 — 9.16.4.85
cisco
secure firewall threat defense
7.0.0 — 7.0.8.1 · 7.1.0 — 7.2.10.2 · 7.3.0 — 7.4.2.4

Mitigating Controls

Control response

Prevent
Stop it (NIST 800-53)

Detect
Catch it (NIST detect / respond)

Harden
Shrink the surface (DISA STIG)
  • 5 hardening rules · 3 OS baselines
Validate
Prove the fix (OWASP ASVS)

Mitigating Controls (NIST 800-53 r5) AI

AC-3 directly requires enforcement of authorization decisions on every access request, structurally eliminating missing authorization checks.

AC-24 mandates that access control decisions are applied to each request, preventing bypass of authorization logic.

AC-25 requires a tamperproof, always-invoked reference monitor that ensures authorization checks cannot be omitted.

AC-6 reduces the set of actions reachable without proper authorization, limiting blast radius of missing checks.

Mitigating Controls (NIST CSF 2.0) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.

PR.AA-05 full match
prevents

Explicitly requires defining, enforcing, and reviewing authorizations and least privilege, directly preventing missing authorization checks.

Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.

prevents

Requiring authentication and credentials before any access occurs eliminates the absence of authorization checks that would otherwise allow an unauthenticated actor to reach protected resources.

prevents

Requiring formal authorization of every access request before rights are granted ensures that checks for required permissions are performed, preventing missing authorization checks from being introduced.

prevents

Mandatory authorization checks and central records of granted rights ensure that every access attempt is preceded by an explicit decision rather than relying on missing checks.

mitigates

Segregating the approval of access rights from their implementation provides an independent check that reduces the impact of missing authorization checks in the resulting system configuration.

finds

By requiring competent outsiders to verify that every function enforces the need-to-know principle, the control lowers the likelihood that missing authorization checks persist undetected.

prevents

Defining authorization responsibilities and reviewing risk-treatment progress throughout the project lifecycle catches missing authorization checks before the system is deployed.

Hardening callouts derived

Configuration rules from DISA STIG baselines that bear on weaknesses of the type cited by this CVE. Each rule is shown with the relationship its mapping actually records, against the CWE it was authored against. Derived via CVE→CWE over `controls_xwalks` (authoritative rows only; rows rated `none` are excluded).

Oracle Linux 8 (2 rules)
  • V-248581 OL 8 must require users to provide a password for privilege escalation. prevents CWE-862
  • V-252656 The OL 8 operating system must not be configured to bypass password requirements for privilege escalation. prevents CWE-862
RHEL 7 (2 rules)
  • V-251704 The Red Hat Enterprise Linux operating system must not be configured to bypass password requirements for privilege escalation. prevents CWE-862
  • V-204429 The Red Hat Enterprise Linux operating system must be configured so that users must provide a password for privilege escalation. prevents CWE-862

References