Security Resilience

CVE-2026-78011

Memory Safety

Published
28 August 2026
Modified
03 September 2026
CVSS Score v4 8.7
Click a component to see what it means
Raw vectorCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
EPSS Score 0.0054 45th percentile
Risk Priority 45 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-2026-78011 is a high-severity Wrap or Wraparound (CWE-191) vulnerability in Watchguard (inferred from references). Its CVSS base score is 8.7 (High).

Operationally, exploitation aligns with the MITRE ATT&CK technique Exploitation of Remote Services (T1210); ranked at the 45th 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-11 (Developer Testing and Evaluation) and SA-15 (Development Process, Standards, and Tools) — see the control section below for these in your framework.

EU & UK References

Vulnerability Data

An integer underflow vulnerability in the WatchGuard Fireware OS iked process allows a remote unauthenticated attacker to create a Denial of Service (DoS) condition in VPN processing by sending specially crafted network traffic.

CWE(s)

Related Threats

MITRE ATT&CK Enterprise Techniques

T1210 Exploitation of Remote Services Lateral Movement
Adversaries may exploit remote services to gain unauthorized access to internal systems once inside of a network.
T1212 Exploitation for Credential Access Credential Access
Adversaries may exploit software vulnerabilities in an attempt to collect credentials.
T1068 Exploitation for Privilege Escalation Privilege Escalation
Adversaries may exploit software vulnerabilities in an attempt to elevate privileges.
T1203 Exploitation for Client Execution Execution
Adversaries may exploit software vulnerabilities in client applications to execute code.
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.
T1211 Exploitation for Stealth Stealth
Adversaries may exploit vulnerabilities to evade detection by hiding activity, suppressing logging, or operating within trusted or unmonitored components.
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2025-29909Shared CWE-191, CWE-787
CVE-2023-24821Shared CWE-191, CWE-787
CVE-2025-30356Shared CWE-191, CWE-787
CVE-2023-33059Shared CWE-191, CWE-787
CVE-2023-24820Shared CWE-191, CWE-787
CVE-2023-32653Shared CWE-191, CWE-787
CVE-2023-24817Shared CWE-191, CWE-787
CVE-2025-29912Shared CWE-191, CWE-787
CVE-2024-55627Shared CWE-191, CWE-787
CVE-2024-47429Shared CWE-787

Affected Assets

Watchguard
—
inferred from references and description; NVD did not file a CPE for this CVE

Mitigating Controls

Mitigating Controls (NIST 800-53 r5) AI

Developer testing and static/dynamic analysis directly find integer underflow defects before code is released.

Requiring documented secure-development standards and tools can mandate bounds-checked coding practices that avoid the weakness.

Security engineering principles require use of safe arithmetic constructs or language features that structurally eliminate integer underflow during subtraction.

Input validation can reject or sanitize values that would cause a subtraction to underflow the representable range.

Memory-protection mechanisms limit the exploitability and blast radius of a successful out-of-bounds write.

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
blocks

Secure SDLC practices directly prevent integer underflow defects via input validation, bounds checking, and static analysis.

ID.RA-01 partial match
blocks

Vulnerability scanning and code analysis can surface underflow flaws after they are introduced.

PR.PS-02 partial match
blocks

Routine patching can remediate known underflow bugs once they are discovered in deployed software.

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 catches integer underflow defects before release.

prevents

Secure coding standards directly prescribe safe integer handling and overflow/underflow prevention.

References