GHSA-vccx-p757-pv6h: Github.com/k1LoW/mo Cross-Site Scripting Vulnerability

LOW
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CWE-79
Published
Advisory Summary

GHSA-vccx-p757-pv6h is a LOW cross-site scripting vulnerability (CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')) affecting Github.com/k1LoW/mo libraries in the Go ecosystem. The issue involves mo has a xss via inline svg script tags in markdown rendering. Remediation is available by upgrading affected packages to version 0.18.5.

GHSA-vccx-p757-pv6h at a Glance

CVE Identifier N/A
GHSA Identifier GHSA-vccx-p757-pv6h
Severity LOW
CVSS v3.1 Base Score N/A
CWE Classification CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
Affected Product Github.com/k1LoW/mo
Package Ecosystem Go
Published Date
Last Updated

How to Fix GHSA-vccx-p757-pv6h

To remediate this vulnerability, upgrade all affected Github.com/k1LoW/mo dependencies to a patched release. Both direct and transitive dependencies should be checked, as frameworks or security libraries may pull in vulnerable versions transitively.

github.com/k1LoW/mo fixed: 0.18.5 
Upgrade github.com/k1LoW/mo to 0.18.5
Verify Direct and Transitive Dependencies

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

inspect dependencies for github.com/k1LoW/mo

How to Check if You Are Affected

To determine whether your application is affected by GHSA-vccx-p757-pv6h, inspect your project dependencies for Github.com/k1LoW/mo:

inspect dependencies for github.com/k1LoW/mo

Analyze the terminal output to locate any version of Github.com/k1LoW/mo in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 0.18.5), your application is affected.

Note: Verify declared build manifests and deployed runtime container environments.

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 Github.com/k1LoW/mo, 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 When rendering Markdown files containing inline SVG elements with `<script>` tags, the embedded JavaScript is executed in the browser. This is due to `rehype-raw` passing raw HTML (including SVG) through to the DOM without sanitization. ### PoC ```html <svg><script>alert(1)</script></svg> ``` Embedding the above in a Markdown file opened with mo causes the script to execute. ### Impact Arbitrary JavaScript execution in the context of the mo application when a user opens a malicious Markdown file. This could lead to data exfiltration of other opened Markdown file contents. ### Remediation Fixed by adding `rehype-sanitize` to the Markdown rendering pipeline, which strips dangerous elements such as `<script>` while preserving safe HTML.

GHSA-vccx-p757-pv6h Affected Github.com/k1LoW/mo Versions

1 component(s)
Fixed Versions:
0.18.5
Product / Package Ecosystem Affected Versions Fixed Version
github.com/k1LoW/mo
golang/github.com/k1LoW/mo
Go
< 0.18.5
0.18.5

References

GitHub Advisory / Wiki ADVISORY
https://github.com/k1LoW/mo/security/advisories/GHSA-vccx-p757-pv6h
Github.com/k1LoW/mo Source Repository REPOSITORY
https://github.com/k1LoW/mo

Frequently Asked Questions

What is GHSA-vccx-p757-pv6h?
GHSA-vccx-p757-pv6h is a security vulnerability in Github.com/k1LoW/mo involving mo has a XSS via inline SVG script tags in Markdown rendering under CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting').
Which Github.com/k1LoW/mo versions are affected?
Affected versions include releases prior to 0.18.5 across affected packages: github.com/k1LoW/mo.
What version fixes GHSA-vccx-p757-pv6h?
Upgrading to 0.18.5 (or the latest patched release for your respective branch) resolves the vulnerability.
Is github.com/k1LoW/mo affected?
Yes, github.com/k1LoW/mo is affected in releases prior to 0.18.5. Upgrade your dependency to 0.18.5 or later.
What CWE is associated with GHSA-vccx-p757-pv6h?
GHSA-vccx-p757-pv6h 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 Go dependencies for GHSA-vccx-p757-pv6h?
Run the dependency tree command: 'inspect dependencies for github.com/k1LoW/mo'. 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
View Raw JSON 
{
  "schema_version" : "1.4.0",
  "id" : "GHSA-vccx-p757-pv6h",
  "modified" : "2026-03-18T20:17:12Z",
  "published" : "2026-03-18T20:17:12Z",
  "aliases" : [ ],
  "summary" : "mo has a XSS via inline SVG script tags in Markdown rendering",
  "details" : "### Summary\n\nWhen rendering Markdown files containing inline SVG elements with `<script>` tags, the embedded JavaScript is executed in the browser. This is due to `rehype-raw` passing raw HTML (including SVG) through to the DOM without sanitization.\n\n### PoC\n\n```html\n<svg><script>alert(1)</script></svg>\n```\n\nEmbedding the above in a Markdown file opened with mo causes the script to execute.\n\n### Impact\n\nArbitrary JavaScript execution in the context of the mo application when a user opens a malicious Markdown file. This could lead to data exfiltration of other opened Markdown file contents.\n\n### Remediation\n\nFixed by adding `rehype-sanitize` to the Markdown rendering pipeline, which strips dangerous elements such as `<script>` while preserving safe HTML.",
  "severity" : [ {
    "type" : "CVSS_V4",
    "score" : "CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:P/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "Go",
      "name" : "github.com/k1LoW/mo"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "0"
      }, {
        "fixed" : "0.18.5"
      } ]
    } ],
    "database_specific" : {
      "last_known_affected_version_range" : "<= 0.18.4"
    }
  } ],
  "references" : [ {
    "type" : "WEB",
    "url" : "https://github.com/k1LoW/mo/security/advisories/GHSA-vccx-p757-pv6h"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/k1LoW/mo"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-79" ],
    "severity" : "LOW",
    "github_reviewed" : true,
    "github_reviewed_at" : "2026-03-18T20:17:12Z",
    "nvd_published_at" : null
  }
}