High severity · published Jun 15, 2026
CVE-2026-12220
Yealink SIP-T46U Firmware Chunk Upload handler accupgradebychunk mod_upgrade.SparePartsUpload stack-based overflow
8.0
CVSS
0.4%
EPSS
No
On KEV
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 and is working on a patch to fix it.
CVSS vector
CVSS:3.1/AV:A/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Attack vector
Adjacent
Complexity
Low
Privileges
Low
User interaction
None
Confidentiality
High
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.4% · higher than 31% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
SI
SIP-T46U · Yealink
108.86.0.118 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-12220
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-12220
cdn2.v50to.cc
http://cdn2.v50to.cc/T46U/T46U_mod_upgrade_SparePartsUpload_stack_overflow.zip
vuldb.com
https://vuldb.com/cve/CVE-2026-12220
vuldb.com
https://vuldb.com/submit/834205
vuldb.com
https://vuldb.com/vuln/370863
vuldb.com
https://vuldb.com/vuln/370863/cti
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