Cyber Resilience

CVE-2018-0101

Memory Safety in Cisco Adaptive Security Appliance Software ≤ 9.1.7.23

Public PoCHigh EPSSMemory Safety
Published
29 January 2018
Modified
11 August 2026
Patch / advisory
CVSS Score v3 10.0
Click a component to see what it means
Raw vectorCVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H
EPSS Score 0.87 99.7th percentile
Risk Priority 100 floored blend · peak EPSS

CVSS and EPSS are reproduced from their sources (NVD, FIRST EPSS). Risk Priority is our own derived reading, not an NVD score.

Summary

CVE-2018-0101 is a critical-severity Double Free (CWE-415) vulnerability in Cisco Adaptive Security Appliance Software. Its CVSS base score is 10.0 (Critical).

Operationally, exploitation aligns with the MITRE ATT&CK technique Exploitation for Client Execution (T1203); ranked in the top 0.3% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.

EU & UK References

Vulnerability Data

A vulnerability in the Secure Sockets Layer (SSL) VPN functionality of the Cisco Adaptive Security Appliance (ASA) Software could allow an unauthenticated, remote attacker to cause a reload of the affected system or to remotely execute code. The vulnerability is…

more

due to an attempt to double free a region of memory when the webvpn feature is enabled on the Cisco ASA device. An attacker could exploit this vulnerability by sending multiple, crafted XML packets to a webvpn-configured interface on the affected system. An exploit could allow the attacker to execute arbitrary code and obtain full control of the system, or cause a reload of the affected device. This vulnerability affects Cisco ASA Software that is running on the following Cisco products: 3000 Series Industrial Security Appliance (ISA), ASA 5500 Series Adaptive Security Appliances, ASA 5500-X Series Next-Generation Firewalls, ASA Services Module for Cisco Catalyst 6500 Series Switches and Cisco 7600 Series Routers, ASA 1000V Cloud Firewall, Adaptive Security Virtual Appliance (ASAv), Firepower 2100 Series Security Appliance, Firepower 4110 Security Appliance, Firepower 9300 ASA Security Module, Firepower Threat Defense Software (FTD). Cisco Bug IDs: CSCvg35618.

CWE(s)

Related Threats

Threat-Actor AttributionAI

ArcaneDoor (C0046)
ArcaneDoor - New espionage-focused campaign found targeting perimeter network devices

MITRE ATT&CK Enterprise Techniques

T1203 Exploitation for Client Execution Execution
Adversaries may exploit software vulnerabilities in client applications to execute code.
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.
T1212 Exploitation for Credential Access Credential Access
Adversaries may exploit software vulnerabilities in an attempt to collect credentials.
T1499 Endpoint Denial of Service Impact
Adversaries may perform Endpoint Denial of Service (DoS) attacks to degrade or block the availability of services to users.
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2024-20494Same product: Cisco Adaptive Security Appliance Software
CVE-2026-20022Same product: Cisco Adaptive Security Appliance Software
CVE-2026-20100Same product: Cisco Adaptive Security Appliance Software
CVE-2024-20408Same product: Cisco Adaptive Security Appliance Software
CVE-2025-20333Same product: Cisco Adaptive Security Appliance Software
CVE-2026-20049Same product: Cisco Adaptive Security Appliance Software
CVE-2024-20402Same product: Cisco Adaptive Security Appliance Software
CVE-2024-20268Same product: Cisco Adaptive Security Appliance Software
CVE-2026-20024Same product: Cisco Adaptive Security Appliance Software
CVE-2025-20182Same product: Cisco Adaptive Security Appliance Software

Affected Assets

cisco
adaptive security appliance software
≤ 9.1.7.23 · 9.2.0 — 9.2.4.27 · 9.3.0 — 9.4.4.16
cisco
secure firewall threat defense
6.0.0, 6.0.1, 6.1.0, 6.2.0, 6.2.1

Mitigating Controls

Control response

Prevent
Stop it (NIST 800-53)

—

Detect
Catch it (NIST detect / respond)

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Harden
Shrink the surface (DISA STIG)
  • 1 hardening rule · 1 OS baseline
Validate
Prove the fix (OWASP ASVS)

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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.PS-06 full match
prevents

Secure SDLC practices directly prevent double-free errors via static analysis, safe memory APIs, and testing.

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.

finds

Security testing in development can detect double-free conditions before release.

prevents

Secure development life cycle includes memory-safety practices that can prevent double-free bugs.

prevents

Application security requirements can mandate memory-safety rules that reduce double-free risk.

prevents

Secure system architecture and engineering principles can prescribe safe memory-management patterns.

prevents

Secure coding standards directly address proper use of free() and similar functions.

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 (1 rule)
  • V-248590 OL 8 must clear the page allocator to prevent use-after-free attacks. prevents CWE-415

References