CVE-2026-88976: @platejs/core @platejs/core HTML Deserialization Can Trigger Vulnerability

MODERATE
Advisory Identifier: GHSA-qrfj-mgw8-j9c6
CVSS 6.1
CWE-79
Published
Advisory Summary

CVE-2026-88976 is a MODERATE (CVSS 6.1) @platejs/core html deserialization can trigger vulnerability (CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')) affecting @platejs/core libraries in the npm ecosystem. The issue involves @platejs/core html deserialization can trigger browser behavior during parsing. Remediation is available by upgrading affected packages to version 53.3.11.

CVE-2026-88976 at a Glance

CVE Identifier CVE-2026-88976
GHSA Identifier GHSA-qrfj-mgw8-j9c6
Severity MODERATE
CVSS v3.1 Base Score 6.1
CWE Classification CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
Affected Product @platejs/core
Package Ecosystem npm
Published Date
Last Updated

Security Impact

CVSS: 6.1

The security impact metrics below are parsed directly from the CVSS v3.1 vector string (CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N).

Attack Vector Network (AV:N)
Attack Complexity Low (AC:L)
Privileges Required None (PR:N)
User Interaction Required (UI:R)
Scope Changed (S:C)
Confidentiality Low (C:L)
Integrity Low (I:L)
Availability None (A:N)

How to Fix CVE-2026-88976

To remediate this vulnerability, upgrade all affected @platejs/core dependencies to a patched release. Both direct and transitive dependencies should be checked, as frameworks or security libraries may pull in vulnerable versions transitively.

@platejs/core fixed: 53.3.11
npm install @platejs/core@53.3.11
@platejs/core fixed: Latest secure release
npm install @platejs/core@Latest secure release
Verify Direct and Transitive Dependencies

Run the following command in your project directory to verify that all resolved dependencies use the patched release:

npm ls @platejs/core

How to Check if You Are Affected

To determine whether your Node.js application is affected by CVE-2026-88976, inspect your project dependencies using npm:

npm ls @platejs/core

Analyze the terminal output to locate any version of @platejs/core in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 53.3.11), your application is affected.

Note: The npm ls @platejs/core command inspects dependencies declared in your package.json and lockfile; it does not perform automated runtime dynamic scanning.

Technical Details

Vulnerability Mechanism & Technical Analysis

This vulnerability is classified under CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting'), where the product does not neutralize or incorrectly neutralizes user-controllable input before it is placed in output that is used as a web page that is served to other users. In @platejs/core, software state validation or input boundaries are circumvented during processing. Review the official source advisory statement below for specific affected components, classes, and reproduction details.

Source Advisory Statement

### Summary HTML strings passed to Plate's core deserialization APIs were parsed in the active document. Certain HTML attributes could therefore trigger browser behavior during parsing, before the content was converted into editor nodes. Applications that deserialize HTML from untrusted or cross-user sources may be affected. ### Impact An attacker who can control HTML later deserialized in another user's browser may be able to execute script in that application's origin. ### Remediation Upgrade to `@platejs/core` 53.3.11 or later. Users of the discontinued 54.0.0 beta builds should install the fixed stable line. Applications should also sanitize untrusted HTML before rendering it; inert parsing is not a substitute for sanitization.

CVE-2026-88976 Affected @platejs/core Versions

2 component(s)
Fixed Versions:
53.3.11
Product / Package Ecosystem Affected Versions Fixed Version
@platejs/core
npm
< 53.3.11
53.3.11
@platejs/core
npm
≥ 54.0.0-beta.0
≤ 54.0.0-beta.1

References

Frequently Asked Questions

What is CVE-2026-88976?
CVE-2026-88976 is a security vulnerability in @platejs/core involving @platejs/core HTML deserialization can trigger browser behavior during parsing under CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting').
Which @platejs/core versions are affected?
Affected versions include releases prior to 53.3.11 across affected packages: @platejs/core.
What version fixes CVE-2026-88976?
Upgrading to 53.3.11 (or the latest patched release for your respective branch) resolves the vulnerability.
Is @platejs/core affected?
Yes, @platejs/core is affected in releases prior to 53.3.11, Latest secure release. Upgrade your dependency to 53.3.11, Latest secure release or later.
What is the CVSS score of CVE-2026-88976?
CVE-2026-88976 has a CVSS v3.1 base score of 6.1 (MODERATE) with vector string CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N.
What CWE is associated with CVE-2026-88976?
CVE-2026-88976 is classified under CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') (The product does not neutralize or incorrectly neutralizes user-controllable input before it is placed in output that is used as a web page that is served to other users.).
How can I check npm dependencies for CVE-2026-88976?
Run the dependency tree command: 'npm ls @platejs/core'. This command lists direct and transitive dependencies in your build configuration so you can verify if a vulnerable version is resolved.
Machine-readable OSV JSON OSV v1.5 Schema
Normalized schema output
{
  "schema_version" : "1.4.0",
  "id" : "GHSA-qrfj-mgw8-j9c6",
  "modified" : "2026-09-17T20:32:47Z",
  "published" : "2026-09-17T20:32:47Z",
  "aliases" : [ "CVE-2026-88976" ],
  "summary" : "@platejs/core HTML deserialization can trigger browser behavior during parsing",
  "details" : "### Summary\n\nHTML strings passed to Plate's core deserialization APIs were parsed in the active document. Certain HTML attributes could therefore trigger browser behavior during parsing, before the content was converted into editor nodes.\n\nApplications that deserialize HTML from untrusted or cross-user sources may be affected.\n\n### Impact\n\nAn attacker who can control HTML later deserialized in another user's browser may be able to execute script in that application's origin.\n\n### Remediation\n\nUpgrade to `@platejs/core` 53.3.11 or later. Users of the discontinued 54.0.0 beta builds should install the fixed stable line. Applications should also sanitize untrusted HTML before rendering it; inert parsing is not a substitute for sanitization.",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "npm",
      "name" : "@platejs/core"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "0"
      }, {
        "fixed" : "53.3.11"
      } ]
    } ]
  }, {
    "package" : {
      "ecosystem" : "npm",
      "name" : "@platejs/core"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "54.0.0-beta.0"
      }, {
        "last_affected" : "54.0.0-beta.1"
      } ]
    } ]
  } ],
  "references" : [ {
    "type" : "WEB",
    "url" : "https://github.com/udecode/plate/security/advisories/GHSA-qrfj-mgw8-j9c6"
  }, {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2026-88976"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/udecode/plate/pull/5117"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/udecode/plate/commit/d02afe45d5ec3a9fb95e0745bc5820ff18a3c12b"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/udecode/plate"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/udecode/plate/releases/tag/v53.3.11"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-79" ],
    "severity" : "MODERATE",
    "github_reviewed" : true,
    "github_reviewed_at" : "2026-09-17T20:32:47Z",
    "nvd_published_at" : "2026-09-16T15:18:05Z"
  }
}