---
id: CVE-2026-88921
title: >-
  MISP contains an HTML injection vulnerability in the
  MISPElementHTMLFormatterTool component, which is responsible for rendering
  MISP element references (attributes, objects, and tags) into inline HTML
  during PDF report export via the con…
summary: >-
  MISP contains an HTML injection vulnerability in the
  MISPElementHTMLFormatterTool component, which is responsible for rendering
  MISP element references (attributes, objects, and tags) into inline HTML
  during PDF report export via the con…
severity: medium
cvss: 5.1
cvssVector: 'CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N'
cwe:
  - CWE-79
  - CWE-116
vendor: MISP
product: MISP
affected:
  - MISP >= unspecified < 2.5.46
published: '2026-09-10'
updated: '2026-09-10'
sourceUpdated: '2026-09-10T17:17:09.360'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-88921'
references:
  - url: 'https://github.com/MISP/MISP/commit/949744a4b'
    label: 5a6e4751-2f3f-4070-9419-94fb35b644e8
tags:
  - nvd
  - cve.org
ssvc:
  exploitation: none
  automatable: 'no'
  technicalImpact: partial
  timestamp: '2026-09-10T17:01:58.906810Z'
cvssSource: cna
ingestedAt: '2026-09-12T14:32:42.864Z'
epss: 0.00492
epssPercentile: 0.39692
---

## Overview

MISP contains an HTML injection vulnerability in the MISPElementHTMLFormatterTool component, which is responsible for rendering MISP element references (attributes, objects, and tags) into inline HTML during PDF report export via the convert_markdown_to_pdf module. The attribute(), objectAttribute(), object(), and tag() methods interpolated user-controlled fields (attribute type, attribute value, object name, object relation, tag name, tag colour, and tag text colour) directly into HTML templates without applying HTML entity encoding. An authenticated user with the ability to create or modify MISP attributes, objects, or tags could embed arbitrary HTML markup in these fields. When a report containing such elements was exported to PDF, the unescaped content was rendered as live HTML rather than inert text, potentially injecting script tags, breaking the document structure, or altering the visual content of the exported report. Additionally, the attribute() method contained a template with hardcoded sample values ("domain-ip" and "google.com") instead of format placeholders, meaning every plain attribute reference in a PDF displayed the sample text rather than the actual indicator value, constituting a data-integrity defect in the exported document. The vulnerability requires an authenticated actor with write access to MISP elements and a subsequent PDF export of a report referencing those elements. The security impact is primarily to the integrity of the exported document and, depending on the HTML-to-PDF rendering engine, potential execution of injected markup during the conversion step.

Version affected: ≤2.5.45

## Remediation

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