CVE-2021-21259

  1. OpenCVE
  2. Vulnerabilities (CVE)
  3. CVE-2021-21259
HedgeDoc is open source software which lets you create real-time collaborative markdown notes. In HedgeDoc before version 1.7.2, an attacker can inject arbitrary JavaScript into a HedgeDoc note, which is executed when the note is viewed in slide mode. Depending on the configuration of the instance, the attacker may not need authentication to create or edit notes. The problem is patched in HedgeDoc 1.7.2. As a workaround, disallow loading JavaScript from 3rd party sites using the `Content-Security-Policy` header. Note that this will break some embedded content.

6.1 /10

CVSS v3 : MEDIUM

V3 Legend

Vector :

Exploitability : 2.8 / Impact : 2.7

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact LOW

Integrity Impact LOW

Availability Impact NONE

Scope CHANGED

4.3 /10

CVSS v2.0 : MEDIUM

V2 Legend

Vector : AV:N/AC:M/Au:N/C:N/I:P/A:N

Exploitability : 8.6 / Impact : 2.9

Access Vector NETWORK

Access Complexity MEDIUM

Authentication NONE

Confidentiality Impact NONE

Integrity Impact PARTIAL

Availability Impact NONE

References
Link Resource
https://github.com/hackmdio/codimd/issues/1648 Exploit Patch Third Party Advisory
https://github.com/hedgedoc/hedgedoc/commit/35b0d39a12aa35f27fba8c1f50b1886706e7efef Patch Third Party Advisory
https://github.com/hedgedoc/hedgedoc/releases/tag/1.7.2 Release Notes Third Party Advisory
https://github.com/hedgedoc/hedgedoc/security/advisories/GHSA-44w9-vm8p-3cxw Third Party Advisory
Configurations

Configuration 1 (hide)

cpe:2.3:a:hedgedoc:hedgedoc:*:*:*:*:*:*:*:*
History

08 Jun 2021, 14:36

Type Values Removed Values Added
References (MISC) https://github.com/hackmdio/codimd/issues/1648 - (MISC) https://github.com/hackmdio/codimd/issues/1648 - Exploit, Patch, Third Party Advisory
CVSS v2 : 4.3
v3 : 7.4 		v2 : 4.3
v3 : 6.1

04 Jun 2021, 16:15

Type Values Removed Values Added
References
  • (MISC) https://github.com/hackmdio/codimd/issues/1648 -
Summary HedgeDoc is open source software which lets you create real-time collaborative markdown notes. In HedgeDoc before version 1.7.2, an attacker can inject arbitrary JavaScript into a HedgeDoc note, which is executed when the note is viewed in slide mode. Depending on the configuration of the instance, the attacker may not need authentication to create or edit notes. The problem is patched in HedgeDoc 1.7.2. ### Workarounds Disallow loading JavaScript from 3rd party sites using the `Content-Security-Policy` header. Note that this will break some embedded content. ### References This issue was discovered by @TobiasHoll and reported to hackmdio/codimd: https://github.com/hackmdio/codimd/issues/1648 ### For more information If you have any questions or comments about this advisory: * Open an topic on our community forum * Join our matrix room HedgeDoc is open source software which lets you create real-time collaborative markdown notes. In HedgeDoc before version 1.7.2, an attacker can inject arbitrary JavaScript into a HedgeDoc note, which is executed when the note is viewed in slide mode. Depending on the configuration of the instance, the attacker may not need authentication to create or edit notes. The problem is patched in HedgeDoc 1.7.2. As a workaround, disallow loading JavaScript from 3rd party sites using the `Content-Security-Policy` header. Note that this will break some embedded content.
Information

Published : 2021-01-22 17:15

Updated : 2024-02-04 21:23

NVD link : CVE-2021-21259

Mitre link : CVE-2021-21259

CVE.ORG link : CVE-2021-21259

JSON object : View

Products Affected

hedgedoc

  • hedgedoc
CWE
CWE-79

Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')