CVE-2026-78011
Fireware OS Integer Underflow in Iked Allows Unauthenticated Denial of Service (DoS)
Description
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.
INFO
Published Date :
Aug. 28, 2026, 2:16 a.m.
Last Modified :
Aug. 28, 2026, 2:16 a.m.
Remotely Exploit :
Yes !
Source :
5d1c2695-1a31-4499-88ae-e847036fd7e3
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS 4.0 | HIGH | 5d1c2695-1a31-4499-88ae-e847036fd7e3 |
Solution
- Update WatchGuard Fireware OS to the latest version.
- Apply security patches for the iked process.
- Monitor VPN processing for anomalies.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-78011.
| URL | Resource |
|---|---|
| https://psirt.watchguard.com/CVE-2026-78011 |
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-78011 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-78011
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-78011 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-78011 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
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New CVE Received by 5d1c2695-1a31-4499-88ae-e847036fd7e3
Aug. 28, 2026
Action Type Old Value New Value Added Description 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. Added CVSS V4.0 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 Added CWE CWE-787 Added CWE CWE-191 Added Affected New affected value received. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2026/78xxx/CVE-2026-78011.json">CVE-2026-78011</a> Added Reference https://psirt.watchguard.com/CVE-2026-78011