Cyber Resilience

CVE-2026-20349

CISA KEVActive ExploitationEUVD Exploited
Published
11 August 2026
Modified
12 August 2026
KEV Added
11 August 2026
CVSS Score v3.1 8.6
Click a component to see what it means
Raw vectorCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H
EPSS Score N/A
Risk Priority 88 floored blend · peak EPSS

Summary

CVE-2026-20349 is a high-severity Heap Inspection (CWE-244) vulnerability in Cisco Secure Firewall (inferred from references). Its CVSS base score is 8.6 (High).

Operationally, exploitation aligns with the MITRE ATT&CK technique OS Credential Dumping (T1003); CISA has added it to the Known Exploited Vulnerabilities catalog.

EU & UK References

Vulnerability Data

A vulnerability in the Remote Access SSL VPN service for Cisco Secure Firewall Adaptive Security Appliance (ASA) Software and Cisco Secure Firewall Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to cause the device to reload unexpectedly, resulting…

more

in a denial of service (DoS) condition.  This vulnerability is due to insufficient error checking when processing HTTP requests. An attacker could exploit this vulnerability by sending a crafted HTTP request to the Remote Access SSL VPN service on an affected device. A successful exploit could allow the attacker to cause the affected device to reload, resulting in a DoS condition.

CWE(s)
CWE-244
KEV Date Added
11 August 2026

Related Threats

MITRE ATT&CK Enterprise Techniques

T1003 OS Credential Dumping Credential Access
Adversaries may attempt to dump credentials to obtain account login and credential material, normally in the form of a hash or a clear text password.
attack.mitre.org →
T1552 Unsecured Credentials Credential Access
Adversaries may search compromised systems to find and obtain insecurely stored credentials.
attack.mitre.org →
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2023-20070Shared CWE-244
CVE-2026-20039Shared CWE-244
CVE-2025-1721Shared CWE-244
CVE-2025-36083Shared CWE-244
CVE-2025-36118Shared CWE-244
CVE-2025-33101Shared CWE-244
CVE-2025-1719Shared CWE-244
CVE-2025-70873Shared CWE-244
CVE-2025-1722Shared CWE-244
CVE-2023-20031Shared CWE-244

Affected Assets

Cisco
Secure Firewall
inferred from references and description; NVD did not file a CPE for this CVE

Mitigating Controls

Likely Mitigating Controls AI

Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.

SC-4 Information in Shared System Resources
addresses: CWE-244

Forces clearing of heap memory contents prior to release, preventing subsequent processes from inspecting prior sensitive data.

SI-12 Information Management and Retention
addresses: CWE-244

Information management requirements drive clearing of sensitive contents from memory prior to release or reuse.

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.DS-10 mostly match
prevents

Explicit example of removing confidential data from process memory directly prevents heap inspection exposure.

PR.PS-06 partial match
prevents

Secure SDLC practices encompass proper sensitive-memory handling but fixing this single CWE does not achieve the control.

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.8.10 Information deletion partial match
prevents

Explicitly requires secure deletion of sensitive data, directly addressing improper heap clearing.

A.8.25 Secure development life cycle partial match
prevents

Secure SDLC processes can incorporate memory-safety requirements but do not specifically mandate heap clearing.

A.8.28 Secure coding partial match
prevents

Mandates secure coding practices that include proper memory sanitization before release.

A.8.27 Secure system architecture and engineering principles none match
none

Secure architecture principles may reduce exposure but do not prescribe explicit heap-clearing techniques.

References