SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityDeferred

CVE-2026-58487

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.

MEDIUM 5.1EPSS 0.49%

Does this matter?

Lower severity and a low EPSS score (0.49%). Track it; it rarely justifies an emergency change on its own.

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.

CVSS 4.0
5.1 MEDIUMCVSS:4.0/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/M
EPSS
0.49% probability · 42th percentile
Public exploits
None in Exploit-DB
CISA KEV
Not listed
Weakness
CWE-79, CWE-116
Source
security-advisories@github.com
EPSS trend
0%3%5%27 October 2026: 0.49%27 October 202627 October 2026

EPSS 0.5% since 27 October 2026; no change recorded yet. Points are recorded when the score first appears and whenever it moves by a percentage point or more.

Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.