CVE-2026-12220 HIGH

CVE-2026-12220: Yealink SIP-T46U Firmware Chunk Upload handler accupgradebychunk mod_upgrade.SparePartsUpload stack-based overflow

Vendor Yealink
Product SIP-T46U
Weakness CWE-121
Published June 15, 2026
Last update June 15, 2026
View on NVD All CVEs

CVSS base score

8.6/10
Attack vector Adjacent
Attack complexity Low
Privileges required Low
User interaction None
Confidentiality —
Integrity —

CVSS vector

CVSS:4.0/AV:A/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:P

What the vulnerability does

01Description

A vulnerability has been found in Yealink SIP-T46U 108.86.0.118. This affects the function mod_upgrade.SparePartsUpload of the file /api/upgrade/accupgradebychunk of the component Firmware Chunk Upload handler. Such manipulation of the argument uid leads to stack-based buffer overflow. The attack can only be initiated within the local network. The exploit has been disclosed to the public and may be used. The vendor was contacted early about this disclosure but did not respond in any way.

Key dates

02Disclosure timeline

June 15, 2026 CVE published
June 15, 2026 Record updated