Cyber Resilience

CVE-2020-3433

Cisco Anyconnect Secure Mobility Client ≤ 4.9.00086

CISA KEVActive ExploitationEUVD ExploitedPublic PoCRansomware-linked
Published
17 August 2020
Modified
12 August 2026
KEV Added
24 October 2022
Patch / advisory
View advisory
CVSS Score v3.1 7.8
Click a component to see what it means
Raw vectorCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
EPSS Score 0.10 95th percentile
Risk Priority 83 floored blend · peak EPSS

Summary

CVE-2020-3433 is a high-severity Uncontrolled Search Path Element (CWE-427) vulnerability in Cisco Anyconnect Secure Mobility Client. Its CVSS base score is 7.8 (High).

Operationally, exploitation aligns with the MITRE ATT&CK technique Path Interception (T1034); ranked in the top 5% of CVEs by exploit likelihood; CISA has added it to the Known Exploited Vulnerabilities catalog; a public proof-of-concept is referenced.

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 interprocess communication channel of Cisco AnyConnect Secure Mobility Client for Windows allows an authenticated local attacker to perform a DLL hijacking attack. The issue stems from insufficient validation of resources loaded by the application at runtime and is tracked under CWE-427. Exploitation occurs when a crafted IPC message is sent to the AnyConnect process, resulting in arbitrary code execution with SYSTEM privileges on the affected Windows system.

An attacker must possess valid local credentials on the Windows host to trigger the flaw. Successful exploitation grants the ability to run arbitrary code at the highest privilege level without further user interaction, affecting confidentiality, integrity, and availability.

The Cisco Security Advisory cisco-sa-anyconnect-dll-F26WwJW provides official guidance on the issue, and the vulnerability appears in CISA's Known Exploited Vulnerabilities catalog, confirming observed in-the-wild activity. Public exploit code has also been shared via Packet Storm.

OWASP Top 10 for Web (2025)

A08:2025 Software or Data Integrity Failures

EU & UK References

Vulnerability Data

A vulnerability in the interprocess communication (IPC) channel of Cisco AnyConnect Secure Mobility Client for Windows could allow an authenticated, local attacker to perform a DLL hijacking attack. To exploit this vulnerability, the attacker would need to have valid credentials…

more

on the Windows system. The vulnerability is due to insufficient validation of resources that are loaded by the application at run time. An attacker could exploit this vulnerability by sending a crafted IPC message to the AnyConnect process. A successful exploit could allow the attacker to execute arbitrary code on the affected machine with SYSTEM privileges. To exploit this vulnerability, the attacker would need to have valid credentials on the Windows system.

CWE(s)
CWE-427
KEV Date Added
24 October 2022

Related Threats

MITRE ATT&CK Enterprise Techniques

T1034 Path Interception Persistence
**This technique has been deprecated.
attack.mitre.org →
T1574.007 Path Interception by PATH Environment Variable Stealth
Adversaries may execute their own malicious payloads by hijacking environment variables used to load libraries.
attack.mitre.org →
T1574.008 Path Interception by Search Order Hijacking Stealth
Adversaries may execute their own malicious payloads by hijacking the search order used to load other programs.
attack.mitre.org →
T1574 Hijack Execution Flow Stealth
Adversaries may execute their own malicious payloads by hijacking the way operating systems run programs.
attack.mitre.org →
T1574.001 DLL Stealth
Adversaries may abuse dynamic-link library files (DLLs) in order to achieve persistence, escalate privileges, and evade defenses.
attack.mitre.org →
T1574.004 Dylib Hijacking Stealth
Adversaries may execute their own payloads by placing a malicious dynamic library (dylib) with an expected name in a path a victim application searches at runtime.
attack.mitre.org →
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2020-3153Same product: Cisco Anyconnect Secure Mobility Clientboth on KEV
CVE-2023-20178Same product: Cisco Anyconnect Secure Mobility Client
CVE-2023-20241Same product: Cisco Anyconnect Secure Mobility Client
CVE-2024-20474Same product: Cisco Anyconnect Secure Mobility Client
CVE-2023-20240Same product: Cisco Anyconnect Secure Mobility Client
CVE-2025-57716Same product class: VPN / SSL gateway
CVE-2024-20430Same vendor: Cisco
CVE-2024-20338Same vendor: Cisco
CVE-2024-20366Same vendor: Cisco
CVE-2020-15505Same product class: VPN / SSL gatewayboth on KEV

Affected Assets

cisco
anyconnect secure mobility client
≤ 4.9.00086

Mitigating Controls

Control response

Prevent
Stop it (NIST 800-53)

—

Detect
Catch it (NIST detect / respond)

—

Harden
Shrink the surface (DISA STIG)
  • 2 hardening rules · 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 mostly match
prevents

Secure-development practices directly address design of search paths and resource loading.

PR.PS-01 partial match
prevents

Hardened configuration baselines can enforce safe search-path settings and reduce exposure.

PR.PS-05 partial match
prevents

Execution allow-listing can block malicious binaries placed in hijackable search locations.

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.

A.8.29 Security testing in development and acceptance mostly match
finds

Security testing can detect uncontrolled search-path issues but does not prevent them by itself.

A.8.19 Installation of software on operational systems partial match
mitigates

Restricting software installation reduces the chance that an attacker-controlled path element is introduced into the search path.

A.8.27 Secure system architecture and engineering principles partial match
mitigates

Secure system architecture and engineering principles require explicit control over search paths and resource locations.

A.8.28 Secure coding partial match
prevents

Secure coding practices directly address the use of fixed or controlled search paths that can be influenced by unintended actors.

A.8.9 Configuration management partial match
prevents

Configuration management can enforce approved search-path settings but does not inherently prevent the weakness.

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-248577 OL 8 must enable kernel parameters to enforce Discretionary Access Control (DAC) on symlinks. prevents CWE-427

References