Security readout for executives and security teams
Plain-English summary
LINE for iOS versions before 10.16.3 had a WebView cross-site scripting issue. A user would need to interact with affected web content, but successful exploitation could expose or alter limited data inside that context.
Executive priority
Treat as a moderate mobile application risk. It does not indicate broad system compromise, but outdated LINE installations should be remediated because the issue affects user-facing web content handling.
Technical view
CVE-2021-36214 is a CWE-79 XSS flaw in LINE client for iOS before 10.16.3, involving a specific header in WebView. CVSS 3.1 is 6.1: network reachable, low complexity, no privileges, user interaction required, changed scope, low confidentiality and integrity impact.
Likely exposure
Exposure is limited to iOS devices running LINE client versions earlier than 10.16.3. Organizations using managed mobile devices should prioritize users who rely on LINE for business communication or open links through LINE.
Exploitation context
The provided sources do not show active exploitation, and the CVE is not listed as KEV. Public disclosure exists via HackerOne, but evidence in the bundle does not establish real-world exploitation.
Researcher notes
The bundle identifies the affected product, fixed version boundary, CWE, CVSS vector, and HackerOne reference. It does not provide detailed exploit conditions beyond WebView, a specific header, and required user interaction.
Mitigation direction
- Upgrade LINE client for iOS to 10.16.3 or later.
- Use MDM or app inventory controls to identify outdated LINE installations.
- Ask users to avoid opening untrusted links inside LINE until updated.
- Check LINE vendor guidance for any additional hardening instructions.
Validation and detection
- Confirm installed LINE for iOS versions across managed devices.
- Verify no managed devices remain below version 10.16.3.
- Review mobile security telemetry for suspicious LINE WebView activity.
- Track CVE and vendor references for updated exploitation or remediation details.
Public sources used
Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.
Conservative CVE-to-ATT&CK context
These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.
ATT&CK lookup starting points
Use these exact CWE pages and searches to review the Glexia ATT&CK library from this CVE's weakness and description context.
CWE-79: User-session and phishing behavior lookup
Client-side and session-facing weaknesses should be reviewed alongside initial-access and user-execution behaviors. Open the exact CWE lookup page first, then review the ATT&CK searches from that MITRE weakness context. This is a Glexia lookup hint, not an official ATT&CK mapping.
Open ATT&CK lookupCVE-2021-36214 mapping review
Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.
Open ATT&CK lookup- Severity
- Medium
- CVSS
- 6.1 (3.1)
- Known Exploited
- No
- Published
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
CNA and ADP enrichment extracted from CVE v5
These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.
CVSS vector scores
1 official scoreWe collect every scored CVSS vector available in the official CNA and ADP containers. When more than one version is present, the table keeps the source vectors side by side instead of collapsing them into the highest score.
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N2.82.7Primary CVE scoreVulnerability scoring details
Base CVSS 3.1 score
6.1MediumVector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
Source materials
- CVE List V5 sourceCVE List V5
- https://hackerone.com/reports/988332CVE reference
Products and packages named in the record
CWE details
CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.
Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.