5.1
MEDIUM CVSS 4.0
CVE-2026-58487
HedgeDoc: Stored HTML injection via email local-part
Description

HedgeDoc is an open source, real-time, collaborative, markdown notes application. Prior to version 1.11.0, due to unsafe handling of the local-part of registered email addresses, HedgeDoc was vulnerable to stored HTML Injection through its publish and slide views. An attacker could register a specially crafted email address and inject arbitrary HTML into pages viewed by other users. HedgeDoc accepted RFC 5321 quoted-string local-parts in email addresses during registration. The local-part was then reused as the user's display name without escaping and rendered into HTML in multiple places, including publish and slide views as well as the collaborative editor. An attacker could break out of an HTML attribute and inject arbitrary markup into the page. While the deployed Content-Security-Policy prevented straightforward inline JavaScript execution, the injected HTML was still sufficient to alter page content and embed attacker-controlled resources such as cross-origin iframes. This issue was fixed in version 1.11.0.

INFO

Published Date :

July 13, 2026, 10:16 p.m.

Last Modified :

July 13, 2026, 10:16 p.m.

Remotely Exploit :

Yes !
Affected Products

The following products are affected by CVE-2026-58487 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

No affected product recoded yet

CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 4.0 MEDIUM [email protected]
Solution
Update HedgeDoc to version 1.11.0 or later to fix stored HTML injection vulnerability.
  • Update HedgeDoc to version 1.11.0 or later.
  • Ensure email address handling is properly escaped.
  • Review and strengthen Content-Security-Policy.
References to Advisories, Solutions, and Tools

Here, you will find a curated list of external links that provide in-depth information, practical solutions, and valuable tools related to CVE-2026-58487.

URL Resource
https://github.com/hedgedoc/hedgedoc/security/advisories/GHSA-6c2w-8w96-3pcv
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-58487 is associated with the following CWEs:

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2026-58487 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2026-58487 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • New CVE Received by [email protected]

    Jul. 13, 2026

    Action Type Old Value New Value
    Added Affected [{'vendor': 'hedgedoc', 'product': 'hedgedoc', 'versions': [{'status': 'affected', 'version': '< 1.11.0'}]}]
    Added Description HedgeDoc is an open source, real-time, collaborative, markdown notes application. Prior to version 1.11.0, due to unsafe handling of the local-part of registered email addresses, HedgeDoc was vulnerable to stored HTML Injection through its publish and slide views. An attacker could register a specially crafted email address and inject arbitrary HTML into pages viewed by other users. HedgeDoc accepted RFC 5321 quoted-string local-parts in email addresses during registration. The local-part was then reused as the user's display name without escaping and rendered into HTML in multiple places, including publish and slide views as well as the collaborative editor. An attacker could break out of an HTML attribute and inject arbitrary markup into the page. While the deployed Content-Security-Policy prevented straightforward inline JavaScript execution, the injected HTML was still sufficient to alter page content and embed attacker-controlled resources such as cross-origin iframes. This issue was fixed in version 1.11.0.
    Added CVSS V4.0 AV:N/AC:L/AT:N/PR:L/UI:P/VC:N/VI:L/VA:N/SC:N/SI:L/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
    Added CWE CWE-79
    Added CWE CWE-116
    Added Reference https://github.com/hedgedoc/hedgedoc/security/advisories/GHSA-6c2w-8w96-3pcv
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.