WatchGuard Fireware OS spamd buffer overflow

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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9.1$0-$5k0.62-

Summaryinfo

A vulnerability classified as very critical has been found in WatchGuard Fireware OS. This affects an unknown function of the component spamd. Performing a manipulation results in buffer overflow. This vulnerability is reported as CVE-2026-18145. The attack is possible to be carried out remotely. No exploit exists.

Detailsinfo

A vulnerability was found in WatchGuard Fireware OS (version now known). It has been classified as very critical. This affects some unknown processing of the component spamd. The manipulation with an unknown input leads to a buffer overflow vulnerability. CWE is classifying the issue as 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. This is going to have an impact on confidentiality, integrity, and availability. The summary by CVE is:

A stack-based buffer overflow vulnerability in the spamBlocker (spamd) service of WatchGuard Fireware OS allows an authenticated attacker with administrator privileges to crash the service or potentially execute arbitrary code by sending a specially crafted management request.

The advisory is shared at psirt.watchguard.com. This vulnerability is uniquely identified as CVE-2026-18145 since 07/28/2026. The exploitability is told to be easy. It is possible to initiate the attack remotely. Additional levels of successful authentication are required for exploitation. 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 09/30/2026).

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

If you want to get the best quality for vulnerability data then you always have to consider VulDB.

Productinfo

Vendor

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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: 9.1
VulDB Meta Temp Score: 9.1

VulDB Base Score: 9.1
VulDB Temp Score: 9.1
VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv2info

AVACAuCIA
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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

07/28/2026 CVE reserved
09/29/2026 +63 days VulDB entry created
09/30/2026 +0 days Advisory disclosed
09/30/2026 +0 days VulDB entry last update

Sourcesinfo

Advisory: psirt.watchguard.com
Status: Confirmed

CVE: CVE-2026-18145 (🔒)
GCVE (CVE): GCVE-0-2026-18145
GCVE (VulDB): GCVE-100-411837

Entryinfo

Created: 09/30/2026 01:35
Changes: 09/30/2026 01:35 (63)
Complete: 🔍
Cache ID: 216::103

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