CVE-2026-12221

A vulnerability was found in Yealink SIP-T46U 108.86.0.118. This impacts the function sprintf of the file /api/upgrade/upgrade of the component Firmware Chunk Upload Handler. Performing a manipulation of the argument uid/start_offset results in stack-based buffer overflow. The attack needs to be approached within the local network. The exploit has been made public and could be used. The vendor was contacted early about this disclosure but did not respond in any way.

CVSS v3 8.0 HIGH
CVSS v2.0 7.7 HIGH

8.0^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.1 / Impact : 5.9

Attack Vector ADJACENT_NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

7.7^/10

CVSS v2.0 : HIGH

Vector : AV:A/AC:L/Au:S/C:C/I:C/A:C

Exploitability : 5.1 / Impact : 10.0

Access Vector ADJACENT_NETWORK

Access Complexity LOW

Authentication SINGLE

Confidentiality Impact COMPLETE

Integrity Impact COMPLETE

Availability Impact COMPLETE

References

Link	Resource
http://cdn2.v50to.cc/T46U/T46U_mod_upgrade_Upgrade_chunk_stack_overflow.zip
https://vuldb.com/cve/CVE-2026-12221
https://vuldb.com/submit/834207
https://vuldb.com/vuln/370864
https://vuldb.com/vuln/370864/cti

Configurations

No configuration.

History

15 Jun 2026, 06:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-06-15 06:16

Updated : 2026-06-15 20:42

NVD link : CVE-2026-12221

Mitre link : CVE-2026-12221

CVE.ORG link : CVE-2026-12221

JSON object : View

Products Affected

No product.

CWE

CWE-119

Improper Restriction of Operations within the Bounds of a Memory Buffer

CWE-121

Stack-based Buffer Overflow

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