Heap-based Buffer Overflow Vulnerability Leading to Denial-of-Service in TP-Link Tapo C520WS
Summary
| CVE | CVE-2026-34118 |
|---|---|
| State | PUBLISHED |
| Assigner | TPLink |
| Source Priority | CVE Program / NVD first with legacy fallback |
| Published | 2026-04-02 18:16:28 UTC |
| Updated | 2026-04-06 20:26:55 UTC |
| Description | A heap-based buffer overflow vulnerability was identified in TP-Link Tapo C520WS v2.6 in the HTTP POST body parsing logic due to missing validation of remaining buffer capacity after dynamic allocation, due to insufficient boundary validation when handling externally supplied HTTP input. An attacker on the same network segment could trigger heap memory corruption conditions by sending crafted payloads that cause write operations beyond allocated buffer boundaries. Successful exploitation causes a Denial-of-Service (DoS) condition, causing the device’s process to crash or become unresponsive. |
Risk And Classification
Primary CVSS: v4.0 7.1 HIGH from f23511db-6c3e-4e32-a477-6aa17d310630
CVSS:4.0/AV:A/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/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
EPSS: 0.000180000 probability, percentile 0.046300000 (date 2026-04-07)
Problem Types: CWE-122 | CWE-122 CWE-122 Heap-based buffer overflow
| Version | Source | Type | Score | Severity | Vector |
|---|---|---|---|---|---|
| 4.0 | f23511db-6c3e-4e32-a477-6aa17d310630 | Secondary | 7.1 | HIGH | CVSS:4.0/AV:A/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/C... |
| 4.0 | CNA | CVSS | 7.1 | HIGH | CVSS:4.0/AV:A/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N |
| 3.1 | [email protected] | Primary | 6.5 | MEDIUM | CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
CVSS v4.0 Breakdown
Attack Vector
AdjacentAttack Complexity
LowAttack Requirements
NonePrivileges Required
NoneUser Interaction
NoneConfidentiality
NoneIntegrity
NoneAvailability
HighSub Conf.
NoneSub Integrity
NoneSub Availability
NoneCVSS:4.0/AV:A/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/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
CVSS v3.1 Breakdown
Attack Vector
AdjacentAttack Complexity
LowPrivileges Required
NoneUser Interaction
NoneScope
UnchangedConfidentiality
NoneIntegrity
NoneAvailability
HighCVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
NVD Known Affected Configurations (CPE 2.3)
| Type | Vendor | Product | Version | Update | Edition | Language |
|---|---|---|---|---|---|---|
| Hardware | Tp-link | Tapo C520ws | 2.6 | All | All | All |
| Operating System | Tp-link | Tapo C520ws Firmware | All | All | All | All |
Vendor Declared Affected Products
| Source | Vendor | Product | Version | Platforms |
|---|---|---|---|---|
| CNA | TP-Link Systems Inc. | Tapo C520WS V2.6 | affected 1.2.4 Build 260326 Rel.24666n custom | Not specified |
References
| Reference | Source | Link | Tags |
|---|---|---|---|
| www.tp-link.com/us/support/faq/5047 | f23511db-6c3e-4e32-a477-6aa17d310630 | www.tp-link.com | Vendor Advisory |
| www.tp-link.com/en/support/download/tapo-c520ws | f23511db-6c3e-4e32-a477-6aa17d310630 | www.tp-link.com | Release Notes |
| www.tp-link.com/us/support/download/tapo-c520ws | f23511db-6c3e-4e32-a477-6aa17d310630 | www.tp-link.com | Release Notes |
| CVE Program record | CVE.ORG | www.cve.org | canonical |
| NVD vulnerability detail | NVD | nvd.nist.gov | canonical, analysis |
No vendor comments have been submitted for this CVE.
There are currently no legacy QID mappings associated with this CVE.