CVE-2021-39175 - CVE House
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Status published High CVE-2021-39175

XSS vector in slide mode speaker-view

Vulnerability Description

HedgeDoc is a platform to write and share markdown. In versions prior to 1.9.0, an unauthenticated attacker can inject arbitrary JavaScript into the speaker-notes of the slide-mode feature by embedding an iframe hosting the malicious code into the slides or by embedding the HedgeDoc instance into another page. The problem is patched in version 1.9.0. There are no known workarounds aside from upgrading.

Impact Analysis

Refer to official advisory for detailed impact metrics.

Remediation

Ensure systems are updated to the latest vendor-supplied patch levels.

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Credits & Attribution

No credits recorded in the NVD database.

References

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Affected Vendor

Affected Software

hedgedoc
Vulnerable Versions:
< 1.9.0

Timeline

Official Publish: August 30th, 2021
Last Modified: August 4th, 2024
Added to House: July 21st, 2026

CVSS Vectors

V3: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:N

Weaknesses (CWE)

CWE-74 CWE-346

MITRE ATT&CK TTPs

T1190 Exploit Public-Facing Application
Initial Access
T1059 Command and Scripting Interpreter
Execution
T1562 Impair Defenses
Defense Evasion
T1213 Data from Information Repositories
Collection
T1189 Drive-by Compromise
Initial Access
T1078 Valid Accounts
Persistence
T1565.002 Stored Data Manipulation
Impact