CVE-2026-28525

SWUpdate contains an integer underflow vulnerability in the multipart upload parser in mongoose_multipart.c that allows unauthenticated attackers to cause a denial of service by sending a crafted HTTP POST request to /upload with a malformed multipart boundary and controlled TCP stream timing. Attackers can trigger an integer underflow in the mg_http_multipart_continue_wait_for_chunk() function when the buffer length falls within a specific range, causing an out-of-bounds heap read past the allocated receive buffer to a local IPC socket.

CVSS v3 6.8 MEDIUM

6.8^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.2 / Impact : 4.0

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope CHANGED

References

Link	Resource
https://github.com/sbabic/swupdate/commit/beee2dc0feef1cfe84f1aa6fc980e104b2e47a74	Patch
https://www.vulncheck.com/advisories/swupdate-integer-underflow-in-multipart-upload-parser	Third Party Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:swupdate:swupdate:*:*:*:*:*:*:*:*

History

26 Oct 2026, 21:10

Type	Values Removed	Values Added
Summary		(es) SWUpdate contiene una vulnerabilidad de desbordamiento negativo de enteros en el analizador de carga multiparte en mongoose_multipart.c que permite a atacantes no autenticados causar una denegación de servicio enviando una solicitud HTTP POST manipulada a /upload con un límite multiparte malformado y una temporización controlada del flujo TCP. Los atacantes pueden desencadenar un desbordamiento negativo de enteros en la función mg_http_multipart_continue_wait_for_chunk() cuando la longitud del búfer cae dentro de un rango específico, causando una lectura de pila fuera de límites que escribe datos más allá del búfer de recepción asignado a un socket IPC local.

Information

Published : 2026-04-23 21:16

Updated : 2026-10-26 21:10

NVD link : CVE-2026-28525

Mitre link : CVE-2026-28525

CVE.ORG link : CVE-2026-28525

JSON object : View

Products Affected

swupdate

swupdate

CWE

CWE-125

Out-of-bounds Read

CWE-191

Integer Underflow (Wrap or Wraparound)

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