CVE-2026-34118 | TP-Link Tapo C520WS 2.6 heap-based overflow (EUVD-2026-18426)

VDB-354959 · CVE-2026-34118 · EUVD-2026-18426 TP-LINK TAPO C520WS 2.6 HEAP-BASED OVERFLOW HISTORYDIFFRELATEJSONXMLCTI CVSS Meta Temp Score Current Exploit Price (≈) CTI Interest Score 8.8 $0-$5k 0.85+ Summaryinfo A vulnerability has been found in TP-Link Tapo C520WS 2.6 and classified as critical. Affected by this vulnerability is an unknown functionality. The manipulation leads to heap-based overflow. This vulnerability is traded as CVE-2026-34118. Access to the local network is required for this attack to succeed. There is no exploit available. Detailsinfo A vulnerability was found in TP-Link Tapo C520WS 2.6. It has been rated as critical. This issue affects an unknown part. The manipulation with an unknown input leads to a heap-based overflow vulnerability. Using CWE to declare the problem leads to CWE-122. A heap overflow condition is a buffer overflow, where the buffer that can be overwritten is allocated in the heap portion of memory, generally meaning that the buffer was allocated using a routine such as malloc(). Impacted is confidentiality, integrity, and availability. The summary by CVE is: 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. It is possible to read the advisory at tp-link.com. The identification of this vulnerability is CVE-2026-34118 since 03/25/2026. The exploitation is known to be easy. The attack needs to be done within the local network. No form of authentication is needed for a successful exploitation. The technical details are unknown and an exploit is not publicly available. The pricing for an exploit might be around USD $0-$5k at the moment (estimation calculated on 04/02/2026). There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product. The vulnerability is also documented in the vulnerability database at EUVD (EUVD-2026-18426). Productinfo Vendor TP-Link Name Tapo C520WS Version 2.6 License commercial Website Vendor: https://www.tp-link.com/ CPE 2.3info 🔒 CPE 2.2info 🔒 CVSSv4info VulDB Vector: 🔒 VulDB Reliability: 🔍 CNA CVSS-B Score: 🔒 CNA CVSS-BT Score: 🔒 CNA Vector: 🔒 CVSSv3info VulDB Meta Base Score: 8.8 VulDB Meta Temp Score: 8.8 VulDB Base Score: 8.8 VulDB Temp Score: 8.8 VulDB Vector: 🔒 VulDB Reliability: 🔍 CVSSv2info Vector Complexity Authentication Confidentiality Integrity Availability Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock VulDB Base Score: 🔒 VulDB Temp Score: 🔒 VulDB Reliability: 🔍 Exploitinginfo Class: Heap-based overflow CWE: CWE-122 / CWE-119 CAPEC: 🔒 ATT&CK: 🔒 Physical: No Local: No Remote: Partially Availability: 🔒 Status: Not defined Price Prediction: 🔍 Current Price Estimation: 🔒 0-Day Unlock Unlock Unlock Unlock Today Unlock Unlock Unlock Unlock Threat Intelligenceinfo Interest: 🔍 Active Actors: 🔍 Active APT Groups: 🔍 Countermeasuresinfo Recommended: no mitigation known Status: 🔍 0-Day Time: 🔒 Timelineinfo 03/25/2026 CVE reserved 04/02/2026 +7 days Advisory disclosed 04/02/2026 +0 days VulDB entry created 04/02/2026 +0 days VulDB entry last update Sourcesinfo Vendor: tp-link.com Advisory: tp-link.com Status: Not defined CVE: CVE-2026-34118 (🔒) GCVE (CVE): GCVE-0-2026-34118 GCVE (VulDB): GCVE-100-354959 EUVD: 🔒 Entryinfo Created: 04/02/2026 19:36 Updated: 04/02/2026 21:15 Changes: 04/02/2026 19:36 (64), 04/02/2026 21:15 (1) Complete: 🔍 Cache ID: 99:0D7:101 Discussion No comments yet. Languages: en. Please log in to comment. ◂ PreviousOverviewNext ▸