CVE-2026-3861 | LINE Client up to 26.2.x on iOS Web denial of service

VDB-357885 · CVE-2026-3861 · GCVE-0-2026-3861 LINE CLIENT UP TO 26.2.X ON IOS WEB DENIAL OF SERVICE HISTORYDIFFRELATEJSONXMLCTI CVSS Meta Temp Score Current Exploit Price (≈) CTI Interest Score 5.3 $0-$5k 1.85 Summaryinfo A vulnerability has been found in LINE Client up to 26.2.x on iOS and classified as problematic. Affected by this vulnerability is an unknown functionality of the component Web Handler. Performing a manipulation results in denial of service. This vulnerability is known as CVE-2026-3861. Remote exploitation of the attack is possible. No exploit is available. The affected component should be upgraded. Detailsinfo A vulnerability classified as problematic has been found in LINE Client up to 26.2.x on iOS. This affects an unknown part of the component Web Handler. The manipulation with an unknown input leads to a denial of service vulnerability. CWE is classifying the issue as CWE-404. The product does not release or incorrectly releases a resource before it is made available for re-use. This is going to have an impact on availability. The summary by CVE is: LINE client for iOS versions prior to 26.3.0 contains a vulnerability in the in-app browser where opening a crafted web page can repeatedly trigger OS-level dialogs, potentially causing the iOS device to become temporarily inoperable. The advisory is shared at hackerone.com. This vulnerability is uniquely identified as CVE-2026-3861 since 03/10/2026. The exploitability is told to be easy. It is possible to initiate the attack remotely. No form of authentication is needed for exploitation. It demands that the victim is doing some kind of user interaction. Neither technical details nor an exploit are publicly available. MITRE ATT&CK project uses the attack technique T1499 for this issue. Upgrading to version 26.3.0 eliminates this vulnerability. Productinfo Type iOS App Software Vendor LINE Name Client Version 26.0 26.1 26.2 CPE 2.3info 🔒 🔒 🔒 CPE 2.2info 🔒 🔒 🔒 CVSSv4info VulDB Vector: 🔒 VulDB Reliability: 🔍 CVSSv3info VulDB Meta Base Score: 5.4 VulDB Meta Temp Score: 5.3 VulDB Base Score: 4.3 VulDB Temp Score: 4.1 VulDB Vector: 🔒 VulDB Reliability: 🔍 CNA Base Score: 6.5 CNA Vector (LY-Corporation): 🔒 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: Denial of service CWE: CWE-404 CAPEC: 🔒 ATT&CK: 🔒 Physical: No Local: No Remote: Yes 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: Upgrade Status: 🔍 0-Day Time: 🔒 Upgrade: Client 26.3.0 Timelineinfo 03/10/2026 CVE reserved 04/16/2026 +36 days Advisory disclosed 04/16/2026 +0 days VulDB entry created 04/16/2026 +0 days VulDB entry last update Sourcesinfo Advisory: hackerone.com Status: Confirmed CVE: CVE-2026-3861 (🔒) GCVE (CVE): GCVE-0-2026-3861 GCVE (VulDB): GCVE-100-357885 Entryinfo Created: 04/16/2026 09:03 Changes: 04/16/2026 09:03 (64) Complete: 🔍 Cache ID: 99:6D3:101 Discussion No comments yet. Languages: en. Please log in to comment. ◂ PreviousOverviewNext ▸