---
id: CVE-2026-120500
title: An Otter Wiki before 2.26.2 Stored XSS via Math Code Block
summary: >-
  An Otter Wiki before 2.26.2 contains a stored cross-site scripting
  vulnerability in OtterwikiMdRenderer.block_code that allows attackers who can
  edit pages, including anonymous users under the default configuration, to
  inject arbitrary s…
severity: medium
cvss: 6.1
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N'
cvssSource: cna
cwe:
  - CWE-79
vendor: redimp
product: otterwiki
affected:
  - otterwiki >= 2.0.0 < 2.26.2
ssvc:
  exploitation: none
  automatable: 'no'
  technicalImpact: partial
  timestamp: '2026-11-02T16:05:05.332198Z'
published: '2026-11-02'
updated: '2026-11-02'
sourceUpdated: '2026-11-02T16:05:16.864Z'
source: CVEORG
sourceUrl: 'https://www.cve.org/CVERecord?id=CVE-2026-120500'
references:
  - url: >-
      https://github.com/redimp/otterwiki/commit/b2e91d20ed36c01ce140d18698f9abb90685d481
  - url: 'https://github.com/redimp/otterwiki/releases/tag/v2.26.2'
    label: otterwiki v2.26.2 Release Notes
  - url: >-
      https://www.vulncheck.com/advisories/an-otter-wiki-before-2.26.2-stored-xss-via-math-code-block
    label: >-
      VulnCheck Advisory: An Otter Wiki before 2.26.2 Stored XSS via Math Code
      Block
tags:
  - cve.org
epss: 0.00288
epssPercentile: 0.21429
ingestedAt: '2026-11-05T19:30:42.701Z'
---

## Overview

An Otter Wiki before 2.26.2 contains a stored cross-site scripting vulnerability in OtterwikiMdRenderer.block_code that allows attackers who can edit pages, including anonymous users under the default configuration, to inject arbitrary script. Attackers can place HTML inside a math fenced code block, which is rendered unescaped and executes for every viewer of the page.

## Affected

- `otterwiki >= 2.0.0 < 2.26.2`

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.