CVE-2026-12220

HIGH

Yealink SIP-T46U Firmware Chunk Upload handler accupgradebychunk mod_upgrade.SparePartsUpload stack-based overflow

Title source: cna
STIX 2.1

Description

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.

References (5)

Core 5
Core References
Vdb Entry, Technical Description vdb-entry technical-description
VDB-370863 | Yealink SIP-T46U Firmware Chunk Upload handler accupgradebychunk mod_upgrade.SparePartsUpload stack-based overflow
https://vuldb.com/vuln/370863
Signature, Permissions Required signature permissions-required
VDB-370863 | CTI Indicators (IOB, IOC, IOA)
https://vuldb.com/vuln/370863/cti
Third Party Advisory third-party-advisory
CVE-2026-12220 | CVE Analysis and Report
https://vuldb.com/cve/CVE-2026-12220
Third Party Advisory third-party-advisory
Submit #834205 | yealink T46U 108.86.0.118 Stack-based Buffer Overflow
https://vuldb.com/submit/834205

Scores

CVSS v3 8.0
EPSS 0.0037
EPSS Percentile 28.7%
Attack Vector ADJACENT_NETWORK
CVSS:3.1/AV:A/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

CISA SSVC

Vulnrichment
Exploitation poc
Automatable no
Technical Impact total

Details

CWE
CWE-119 CWE-121
Status published
Products (1)
Yealink/SIP-T46U 108.86.0.118
Published Jun 15, 2026
Tracked Since Jun 15, 2026