CVE-2026-12221

Exploitation

Assessed, none found. CISA's assessment recorded neither public exploit code nor evidence of exploitation when it was made.

SSVC decision

• ExploitationnoneCISA recorded no public exploit code and no evidence of exploitation.
• AutomatablenoAt least one step from reconnaissance to exploitation cannot be reliably automated.
• Technical ImpacttotalSuccessful exploitation gives total control of the vulnerable component.

CISA publishes the decision points, not a final SSVC decision. The decision also depends on mission and well-being impact, which is a property of your deployment rather than of the vulnerability.

EPSS probability

0.37% probability of exploitation activity in the next 30 days.

EPSS percentile

Ranks above 30.1% of scored records. A rank, not a probability.

NVD base score

7.3 (CVSS v4.0), scored by the NVD independently of the CNA.

NVD 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/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

NVD analysis status

Deferred. NVD last modified this record on 2026-07-24.

Red Hat severity

No Red Hat rating. Red Hat rates the CVEs that affect its products.

Exploit-prediction scores from FIRST. Independent scoring and analysis status from the NVD. Vendor severity from Red Hat. Exploitation assessment and catalog membership from CISA.

Published

2026-06-15 05:00Z2 MO AGO

Last updated

2026-06-27 05:45Z2 MO AGO

Reserved

2026-06-14

Assigning CNA

VulDB

Record state

PUBLISHED

Severity

High (CVSS 8.6)

CNA 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

Weaknesses

• CWE-119Improper Restriction of Operations within the Bounds of a Memory BufferClass
• CWE-121Stack-based Buffer OverflowVariant

Data version

5.2

Document digest

ecc4744315c2d60116fba35e01607f48422ca4d896d24e17f46192d14f501e8c

• vuldb.comVDB-370864 | Yealink SIP-T46U Firmware Chunk Upload upgrade sprintf stack-based overflowhttps://vuldb.com/vuln/370864vdb-entrytechnical-description
• vuldb.comVDB-370864 | CTI Indicators (IOB, IOC, IOA)https://vuldb.com/vuln/370864/ctisignaturepermissions-required
• vuldb.comCVE-2026-12221 | CVE Analysis and Reporthttps://vuldb.com/cve/CVE-2026-12221third-party-advisory
• vuldb.comSubmit #834207 | yealink T46U 108.86.0.118 Stack-based Buffer Overflowhttps://vuldb.com/submit/834207third-party-advisory
• cdn2.v50to.cchttp://cdn2.v50to.cc/T46U/T46U_mod_upgrade_Upgrade_chunk_stack_overflow.zipbroken-linkexploitpatch