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CVE Record

CVE-2021-4325: NHN TOAST UI Chart Legend cross site scripting

A vulnerability, which was classified as problematic, has been found in NHN TOAST UI Chart 4.1.4. This issue affects some unknown processing of the component Legend Handler. The manipulation leads to cross site scripting. The attack may be initiated remotely. Upgrading to version 4.2.0 is able to address this issue. The identifier of the patch is 1a3f455d17df379e11b501bb5ba1dd1bcc41d63e. It is recommended to upgrade the affected component. The identifier VDB-221501 was assigned to this vulnerability.

MediumCVSS 4Not KEV-listedUpdated
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Glexia's TakeAutomated analysismoderate

Security readout for executives and security teams

Plain-English summary

CVE-2021-4325 is a cross-site scripting flaw in NHN TOAST UI Chart 4.1.4, affecting the Legend Handler. A remote authenticated attacker could manipulate chart legend handling so browser-side script runs in a user's session. The cited fix is upgrading TOAST UI Chart to 4.2.0.

Executive priority

Prioritize during the next normal application security patch cycle unless the library is exposed in authenticated workflows with user-controlled chart data. The business risk is session-level browser manipulation, not server compromise based on the provided evidence.

Technical view

The issue is CWE-79 XSS in NHN TOAST UI Chart 4.1.4 Legend Handler processing. The CVSS v2 vector is AV:N/AC:L/Au:S/C:N/I:P/A:N, indicating network reachability, low complexity, required authentication, partial integrity impact, and no stated confidentiality or availability impact. Patch commit 1a3f455d17df379e11b501bb5ba1dd1bcc41d63e is tied to release 4.2.0.

Likely exposure

Exposure is likely limited to applications that bundle or depend on NHN TOAST UI Chart 4.1.4 and render chart legends where attacker-controlled or user-supplied content can reach the affected processing path. Systems not using this library, or already on 4.2.0 or later, are not indicated as affected by the provided sources.

Exploitation context

The sources describe remote initiation and authenticated access, but do not show public exploitation or inclusion in CISA KEV. The CVE record marks KEV as false in the supplied bundle. Treat this as a realistic application-layer XSS risk, not confirmed active exploitation.

Researcher notes

Evidence identifies affected version 4.1.4, fixed version 4.2.0, CWE-79, and a specific patch commit. The vulnerable Legend Handler processing is not fully detailed in the bundle, so validation should focus on dependency presence, rendered legend data sources, and deployed bundle versions.

Mitigation direction

  • Upgrade NHN TOAST UI Chart from 4.1.4 to 4.2.0 or later.
  • Confirm the deployed application uses the patched package, not only updated source control.
  • Check vendor release notes and patch commit for any integration impacts.
  • Until upgraded, avoid rendering untrusted data in affected chart legend contexts.
  • Track this in dependency management until all bundles are rebuilt and redeployed.

Validation and detection

  • Search dependency manifests and lockfiles for NHN TOAST UI Chart version 4.1.4.
  • Inspect production JavaScript bundles for embedded or vendored TOAST UI Chart 4.1.4 code.
  • Verify the deployed package resolves to 4.2.0 or later after remediation.
  • Review routes or components that render chart legends with user-controlled data.
  • Run regression tests for chart rendering after the dependency upgrade.
Prepared
Confidence
high
Sources
7

Public sources used

Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.

Potential ATT&CK relevance

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 · medium confidence lookup

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.

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cve · low confidence lookup

CVE-2021-4325 mapping review

Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.

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Vulnerability profileCVE Program record
Severity
Medium
CVSS
4 (2.0)
Known Exploited
No
Published

Vector: AV:N/AC:L/Au:S/C:N/I:P/A:N

Official CVE source material

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.

1CVSS vectors
0Timeline events
0ADP providers
6Source links

CVSS vector scores

1 official score

We 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.

ScoreVersionSeverityVectorExploitImpactSource
4CVSS 2.0MediumAV:N/AC:L/Au:S/C:N/I:P/A:N82.9Primary CVE score

Vulnerability scoring details

Base CVSS 2.0 score

4Medium
CVSS 2.0 vector shape for CVE-2021-4325Access VectorAccess ComplexityAuthenticationConfidentiality ImpactIntegrity ImpactAvailability Impact

Vector: AV:N/AC:L/Au:S/C:N/I:P/A:N

Access Vector
NetworkAdjacentLocal
Access Complexity
LowMediumHigh
Authentication
NoneSingleMultiple
Confidentiality Impact
CompletePartialNone
Integrity Impact
CompletePartialNone
Availability Impact
CompletePartialNone

Source materials

Affected products

Products and packages named in the record

VendorProductVersion / packageStatus
NHNTOAST UI Chart4.1.4Listed
Weakness

CWE details

CWE-79

CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.