CVE-2026-34866 | Huawei HarmonyOS 6.0.0 Web Module buffer overflow

VDB-357101 · CVE-2026-34866 · GCVE-0-2026-34866 HUAWEI HARMONYOS 6.0.0 WEB MODULE BUFFER OVERFLOW HISTORYDIFFRELATEJSONXMLCTI CVSS Meta Temp Score Current Exploit Price (≈) CTI Interest Score 5.2 $5k-$25k 0.38+ Summaryinfo A vulnerability has been found in Huawei HarmonyOS 6.0.0 and classified as critical. This affects an unknown function of the component Web Module. The manipulation leads to buffer overflow. This vulnerability is documented as CVE-2026-34866. The attack needs to be performed locally. There is not any exploit available. Detailsinfo A vulnerability was found in Huawei HarmonyOS 6.0.0. It has been rated as critical. This issue affects an unknown part of the component Web Module. The manipulation with an unknown input leads to a buffer overflow vulnerability. Using CWE to declare the problem leads to CWE-120. The product copies an input buffer to an output buffer without verifying that the size of the input buffer is less than the size of the output buffer, leading to a buffer overflow. Impacted is confidentiality, integrity, and availability. The summary by CVE is: Out-of-bounds write vulnerability in the WEB module.Impact: Successful exploitation of this vulnerability will affect availability and confidentiality. The advisory is shared at consumer.huawei.com. The identification of this vulnerability is CVE-2026-34866 since 03/31/2026. The exploitation is known to be easy. An attack has to be approached locally. Neither technical details nor an exploit are publicly available. The price for an exploit might be around USD $5k-$25k at the moment (estimation calculated on 04/13/2026). There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product. Productinfo Type Smartphone Operating System Vendor Huawei Name HarmonyOS Version 6.0.0 License commercial Website Vendor: https://www.huawei.com/ CPE 2.3info 🔒 CPE 2.2info 🔒 CVSSv4info VulDB Vector: 🔒 VulDB Reliability: 🔍 CVSSv3info VulDB Meta Base Score: 5.2 VulDB Meta Temp Score: 5.2 VulDB Base Score: 5.3 VulDB Temp Score: 5.3 VulDB Vector: 🔒 VulDB Reliability: 🔍 CNA Base Score: 5.1 CNA Vector (huawei): 🔒 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: Buffer overflow CWE: CWE-120 / CWE-119 CAPEC: 🔒 ATT&CK: 🔒 Physical: Partially Local: Yes Remote: No 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 03/31/2026 CVE reserved 04/13/2026 +13 days Advisory disclosed 04/13/2026 +0 days VulDB entry created 04/13/2026 +0 days VulDB entry last update Sourcesinfo Vendor: huawei.com Advisory: consumer.huawei.com Status: Confirmed CVE: CVE-2026-34866 (🔒) GCVE (CVE): GCVE-0-2026-34866 GCVE (VulDB): GCVE-100-357101 Entryinfo Created: 04/13/2026 09:43 Changes: 04/13/2026 09:43 (63) Complete: 🔍 Cache ID: 99:215:101 Discussion No comments yet. Languages: en. Please log in to comment. ◂ PreviousOverviewNext ▸