CVE-2021-25978: Apostrophe Cross-Site Scripting Vulnerability

MODERATE
Advisory Identifier: GHSA-4r9c-jghc-cx5m
CVSS 5.4
CWE-79
Published
Advisory Summary

CVE-2021-25978 is a MODERATE (CVSS 5.4) cross-site scripting vulnerability (CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')) affecting Apostrophe libraries in the npm ecosystem. The issue involves cross-site scripting in apostrophe. Remediation is available by upgrading affected packages to version 3.4.0.

CVE-2021-25978 at a Glance

CVE Identifier CVE-2021-25978
GHSA Identifier GHSA-4r9c-jghc-cx5m
Severity MODERATE
CVSS v3.1 Base Score 5.4
CWE Classification CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
Affected Product Apostrophe
Package Ecosystem npm
Published Date
Last Updated

Security Impact

CVSS: 5.4

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

Attack Vector Network (AV:N)
Attack Complexity Low (AC:L)
Privileges Required Low (PR:L)
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-2021-25978

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

apostrophe fixed: 3.4.0
npm install apostrophe@3.4.0
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 apostrophe

How to Check if You Are Affected

To determine whether your Node.js application is affected by CVE-2021-25978, inspect your project dependencies using npm:

npm ls apostrophe

Analyze the terminal output to locate any version of Apostrophe in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 3.4.0), your application is affected.

Note: The npm ls apostrophe 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 Apostrophe, 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

Apostrophe CMS versions between 2.63.0 to 3.3.1 are vulnerable to Stored XSS where an editor uploads an SVG file that contains malicious JavaScript onto the Images module, which triggers XSS once viewed.

CVE-2021-25978 Affected Apostrophe Versions

1 component(s)
Fixed Versions:
3.4.0
Product / Package Ecosystem Affected Versions Fixed Version
apostrophe
npm
≥ 2.63.0
< 3.4.0
3.4.0

References

Frequently Asked Questions

What is CVE-2021-25978?
CVE-2021-25978 is a security vulnerability in Apostrophe involving Cross-site Scripting in apostrophe under CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting').
Which Apostrophe versions are affected?
Affected versions include releases prior to 3.4.0 across affected packages: apostrophe.
What version fixes CVE-2021-25978?
Upgrading to 3.4.0 (or the latest patched release for your respective branch) resolves the vulnerability.
Is apostrophe affected?
Yes, apostrophe is affected in releases prior to 3.4.0. Upgrade your dependency to 3.4.0 or later.
What is the CVSS score of CVE-2021-25978?
CVE-2021-25978 has a CVSS v3.1 base score of 5.4 (MODERATE) with vector string CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N.
What CWE is associated with CVE-2021-25978?
CVE-2021-25978 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-2021-25978?
Run the dependency tree command: 'npm ls apostrophe'. 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-4r9c-jghc-cx5m",
  "modified" : "2021-11-08T21:26:37Z",
  "published" : "2021-11-10T16:45:34Z",
  "aliases" : [ "CVE-2021-25978" ],
  "summary" : "Cross-site Scripting in apostrophe",
  "details" : "Apostrophe CMS versions between 2.63.0 to 3.3.1 are vulnerable to Stored XSS where an editor uploads an SVG file that contains malicious JavaScript onto the Images module, which triggers XSS once viewed.",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "npm",
      "name" : "apostrophe"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "2.63.0"
      }, {
        "fixed" : "3.4.0"
      } ]
    } ]
  } ],
  "references" : [ {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2021-25978"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/apostrophecms/apostrophe/commit/c8b94ee9c79468f1ce28e31966cb0e0839165e59"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/apostrophecms/apostrophe"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-79" ],
    "severity" : "MODERATE",
    "github_reviewed" : true,
    "github_reviewed_at" : "2021-11-08T21:26:37Z",
    "nvd_published_at" : "2021-11-07T18:15:00Z"
  }
}