Pre-Authentication Stack-based Buffer Overflow Remote Code Execution in TDDPv2 Subtype 0x91 on Deco M9 Plus
Summary
| CVE | CVE-2026-8618 |
|---|---|
| State | PUBLISHED |
| Assigner | TPLink |
| Source Priority | CVE Program / NVD first with legacy fallback |
| Published | 2026-10-01 19:17:25 UTC |
| Updated | 2026-10-01 20:36:38 UTC |
| Description | A stack-based buffer overflow vulnerability exists in the TDDPv2 service (/usr/bin/tddp) on Deco M9 Plus due to insufficient validation of decrypted request data length before it is copied into a fixed-size stack buffer in the subtype 0x91 handler. Successful exploitation may allow an adjacent, unauthenticated attacker to cause a denial of service or achieve arbitrary code execution during the device setup phase through crafted TDDP packets. |
Risk And Classification
Primary CVSS: v4.0 7.7 HIGH from f23511db-6c3e-4e32-a477-6aa17d310630
CVSS:4.0/AV:A/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:L/SI:L/SA:L/E:X/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
Problem Types: CWE-121 | CWE-121 CWE-121 Stack-based buffer overflow
| Version | Source | Type | Score | Severity | Vector |
|---|---|---|---|---|---|
| 4.0 | f23511db-6c3e-4e32-a477-6aa17d310630 | Secondary | 7.7 | HIGH | CVSS:4.0/AV:A/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:L/SI:L/SA:L/E:X/C... |
| 4.0 | CNA | CVSS | 7.7 | HIGH | CVSS:4.0/AV:A/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:L/SI:L/SA:L |
CVSS v4.0 Breakdown
Attack Vector
AdjacentAttack Complexity
LowAttack Requirements
PresentPrivileges Required
NoneUser Interaction
NoneConfidentiality
HighIntegrity
HighAvailability
HighSub Conf.
LowSub Integrity
LowSub Availability
LowCVSS:4.0/AV:A/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:L/SI:L/SA:L/E:X/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
Vendor Declared Affected Products
| Source | Vendor | Product | Version | Platforms |
|---|---|---|---|---|
| CNA | TP-Link Systems Inc. | Deco M9 Plus V2 | affected 1.9.2 Build 20260818 custom | Not specified |
References
| Reference | Source | Link | Tags |
|---|---|---|---|
| www.tp-link.com/us/support/download/deco-m9-plus/v2 | f23511db-6c3e-4e32-a477-6aa17d310630 | www.tp-link.com | |
| www.tp-link.com/us/support/faq/5322 | f23511db-6c3e-4e32-a477-6aa17d310630 | www.tp-link.com | |
| www.tp-link.com/en/support/download/deco-m9-plus/v2 | f23511db-6c3e-4e32-a477-6aa17d310630 | www.tp-link.com | |
| CVE Program record | CVE.ORG | www.cve.org | canonical |
| NVD vulnerability detail | NVD | nvd.nist.gov | canonical, analysis |
Vendor Comments And Credit
Discovery Credit
CNA: Isa Roovers (en)
There are currently no legacy QID mappings associated with this CVE.