WatchGuard Fireware OS iked buffer overflow

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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4.5$0-$5k0.64

Summaryinfo

A vulnerability marked as problematic has been reported in WatchGuard Fireware OS. This impacts an unknown function of the component iked. The manipulation leads to buffer overflow. This vulnerability is traded as CVE-2026-81851. It is possible to initiate the attack remotely. There is no exploit available.

Detailsinfo

A vulnerability was found in WatchGuard Fireware OS (the affected version is unknown). It has been rated as problematic. This issue affects an unknown code of the component iked. The manipulation with an unknown input leads to a buffer overflow vulnerability. Using CWE to declare the problem leads to CWE-120. The product copies an input buffer to an output buffer without verifying that the size of the input buffer is less than the size of the output buffer, leading to a buffer overflow. Impacted is availability. The summary by CVE is:

A heap-based buffer overflow vulnerability in Fireware OS's iked process allows an authenticated administrator to crash the IKE daemon (iked), resulting in a denial of service, by saving a specially crafted configuration.

The advisory is shared at psirt.watchguard.com. The identification of this vulnerability is CVE-2026-81851 since 08/27/2026. The exploitation is known to be easy. The attack may be initiated remotely. Additional levels of successful authentication are needed for exploitation. It demands that the victim is doing some kind of user interaction. Neither technical details nor an exploit are publicly available. The price for an exploit might be around USD $0-$5k at the moment (estimation calculated on 08/28/2026).

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Productinfo

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License

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA CVSS-B Score: 🔒
CNA CVSS-BT Score: 🔒
CNA Vector: 🔒

CVSSv3info

VulDB Meta Base Score: 4.5
VulDB Meta Temp Score: 4.5

VulDB Base Score: 4.5
VulDB Temp Score: 4.5
VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv2info

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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Buffer overflow
CWE: CWE-120 / CWE-119
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined
Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: no mitigation known
Status: 🔍

0-Day Time: 🔒

Timelineinfo

08/27/2026 CVE reserved
08/28/2026 +1 days Advisory disclosed
08/28/2026 +0 days VulDB entry created
08/28/2026 +0 days VulDB entry last update

Sourcesinfo

Advisory: psirt.watchguard.com
Status: Confirmed

CVE: CVE-2026-81851 (🔒)
GCVE (CVE): GCVE-0-2026-81851
GCVE (VulDB): GCVE-100-396449

Entryinfo

Created: 08/28/2026 02:04
Changes: 08/28/2026 02:04 (63)
Complete: 🔍
Cache ID: 216::103

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

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