Stack-Based Buffer Overflow in the Mercusys MB115-4G

MITRE NVD CVE.ORG JSON API

Summary

CVECVE-2026-12495
StatePUBLISHED
AssignerINCIBE
Source PriorityCVE Program / NVD first with legacy fallback
Published2026-07-27 12:16:41 UTC
Updated2026-07-28 08:17:14 UTC
DescriptionDenial-of-service (DoS) vulnerability due to a stack buffer overflow in the http_gdpr_decrypt function of the Mercusys MB115-4G device's web interface. An unauthenticated attacker could exploit this vulnerability by sending a specially crafted request to the /cgi/login endpoint, causing memory corruption and the httpd process to crash, resulting in a denial of service for the web administration service.

Risk And Classification

Primary CVSS: v4.0 5.3 MEDIUM from [email protected]

CVSS:4.0/AV:A/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/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: 0.001620000 probability, percentile 0.058780000 (date 2026-07-29)

Problem Types: CWE-121 | CWE-121 CWE-121 Stack-based buffer overflow

VersionSourceTypeScoreSeverityVector
4.0[email protected]Secondary5.3MEDIUMCVSS:4.0/AV:A/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:X/C...
4.0CNACVSS5.3MEDIUMCVSS:4.0/AV:A/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N

CVSS v4.0 Breakdown

Attack Vector
Adjacent
Attack Complexity
Low
Attack Requirements
None
Privileges Required
None
User Interaction
None
Confidentiality
None
Integrity
None
Availability
Low
Sub Conf.
None
Sub Integrity
None
Sub Availability
None

CVSS:4.0/AV:A/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/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

Vendor Declared Affected Products

SourceVendorProductVersionPlatforms
CNA Mercusys MB115-4G affected 1.7.0 1.9.0 custom Not specified

References

ReferenceSourceLinkTags
www.incibe.es/en/incibe-cert/notices/aviso/stack-based-buffer-overflow-merc... [email protected] www.incibe.es
CVE Program record CVE.ORG www.cve.org canonical
NVD vulnerability detail NVD nvd.nist.gov canonical, analysis

Vendor Comments And Credit

Discovery Credit

CNA: Héctor Villar Palacios (en)

Additional Advisory Data

Solutions

CNA: The vulnerability has been fixed by the Mercusys team in version V1_1.9.0.

© CVE.report 2026

Use of this information constitutes acceptance for use in an AS IS condition. There are NO warranties, implied or otherwise, with regard to this information or its use. Any use of this information is at the user's risk. It is the responsibility of user to evaluate the accuracy, completeness or usefulness of any information, opinion, advice or other content. EACH USER WILL BE SOLELY RESPONSIBLE FOR ANY consequences of his or her direct or indirect use of this web site. ALL WARRANTIES OF ANY KIND ARE EXPRESSLY DISCLAIMED. This site will NOT BE LIABLE FOR ANY DIRECT, INDIRECT or any other kind of loss.

CVE, CWE, and OVAL are registred trademarks of The MITRE Corporation and the authoritative source of CVE content is MITRE's CVE web site. This site includes MITRE data granted under the following license.

Free CVE JSON API cve.report/api

CVE.report and Source URL Uptime Status status.cve.report