Cyber Resilience

CVE-2026-20068

Cisco Unified Threat Defense Snort Intrusion Prevention System Engine 17.10.1a … 17.9.8

Published
04 March 2026
Modified
18 August 2026
Patch / advisory
View advisory
CVSS Score v3.1 5.8
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:L
EPSS Score 0.0041 34th percentile
Risk Priority 46 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-2026-20068 is a medium-severity Uncaught Exception (CWE-248) vulnerability in Cisco Unified Threat Defense Snort Intrusion Prevention System Engine. Its CVSS base score is 5.8 (Medium).

Operationally, exploitation aligns with the MITRE ATT&CK technique Endpoint Denial of Service (T1499); ranked at the 34th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.

The strongest mitigations our analysis identified map to SA-8 (Security and Privacy Engineering Principles) and SC-24 (Fail in Known State) — see the control section below for these in your framework.

OWASP Top 10 for Web (2025)

A10:2025 Mishandling of Exceptional Conditions

EU & UK References

Vulnerability Data

Multiple Cisco products are affected by a vulnerability in the Snort 3 detection engine that could allow an unauthenticated, remote attacker to cause the Snort 3 Detection Engine to restart, resulting in an interruption of packet inspection. This vulnerability is…

more

due to incomplete error checking when parsing remote procedure call (RPC) data. An attacker could exploit this vulnerability by sending crafted RPC packets through an established connection to be parsed by Snort 3. A successful exploit could allow the attacker to cause a DoS condition when the Snort 3 Detection Engine unexpectedly restarts.

CWE(s)
CWE-248

Related Threats

MITRE ATT&CK Enterprise Techniques

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.
attack.mitre.org →
T1499.004 Application or System Exploitation Impact
Adversaries may exploit software vulnerabilities that can cause an application or system to crash and deny availability to users.
attack.mitre.org →
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2026-20054Same product: Cisco Cyber Vision
CVE-2026-20057Same product: Cisco Cyber Vision
CVE-2023-20086Same product: Cisco Secure Firewall Threat Defense
CVE-2025-20171Same vendor: Cisco
CVE-2025-20172Same vendor: Cisco
CVE-2025-20176Same vendor: Cisco
CVE-2026-20053Same product: Cisco Cyber Vision
CVE-2024-20276Same vendor: Cisco
CVE-2026-20065Same product: Cisco Secure Firewall Threat Defense
CVE-2026-20067Same product: Cisco Cyber Vision

Affected Assets

cisco
snort
3.0.0-233 — 3.9.2.0
cisco
cyber vision
3.0.0, 3.0.1, 3.0.2, 3.0.3, 3.0.4
cisco
secure firewall threat defense
7.2.10, 7.2.10.2, 7.2.4, 7.2.4.1, 7.2.5
cisco
unified threat defense snort intrusion prevention system engine
17.10.1a, 17.11.1a, 17.12.1a, 17.12.2, 17.12.3

Mitigating Controls

Mitigating Controls (NIST 800-53 r5) AI

SA-8 Security and Privacy Engineering Principles partial match

Security engineering principles include robust exception management to keep the system in a defined state.

SC-24 Fail in Known State partial match

Fail-in-known-state reduces the impact when an uncaught exception occurs by preserving a safe condition.

SI-11 Error Handling partial match

Error handling requirements force structured catching and response to exceptions instead of allowing them to propagate uncaught.

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 SDLC practices explicitly require structured exception handling to prevent uncaught exceptions from reaching production.

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 uncaught exceptions before production deployment.

A.8.25 Secure development life cycle partial match
prevents

Secure development lifecycle includes exception-handling standards that reduce uncaught exceptions.

A.8.26 Application security requirements partial match
prevents

Application security requirements typically mandate robust error and exception handling.

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

Secure architecture principles call for centralized, comprehensive exception management.

A.8.28 Secure coding partial match
prevents

Secure coding standards directly require catching and handling exceptions to prevent crashes or leaks.

References