Zulip Server up to 2.1.2 Markdown improper restriction of rendered ui layers

CVSS Meta Temp Score
CVSS is a standardized scoring system to determine possibilities of attacks. The Temp Score considers temporal factors like disclosure, exploit and countermeasures. The unique Meta Score calculates the average score of different sources to provide a normalized scoring system.
Current Exploit Price (≈)
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CTI Interest Score
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A vulnerability, which was classified as critical, has been found in Zulip Server up to 2.1.2. Affected by this issue is an unknown part. The manipulation as part of a Markdown leads to a privilege escalation vulnerability. Using CWE to declare the problem leads to CWE-269. Impacted is confidentiality, and integrity. CVE summarizes:

Zulip Server before 2.1.3 allows reverse tabnabbing via the Markdown functionality.

The weakness was released 04/20/2020 (Website). The advisory is shared for download at blog.zulip.org. This vulnerability is handled as CVE-2020-9444 since 02/28/2020. The attack may be launched remotely. No form of authentication is required for exploitation. Successful exploitation requires user interaction by the victim. There are neither technical details nor an exploit publicly available.

Upgrading to version 2.1.3 eliminates this vulnerability.

Entries connected to this vulnerability are available at 154108 and 154137.




CPE 2.3infoedit

CPE 2.2infoedit


VulDB Meta Base Score: 6.1
VulDB Meta Temp Score: 5.9

VulDB Base Score: 6.1
VulDB Temp Score: 5.8
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 6.1
NVD Vector: 🔍



VulDB Base Score: 🔍
VulDB Temp Score: 🔍
VulDB Reliability: 🔍

NVD Base Score: 🔍


Class: Privilege escalation
CWE: CWE-1021
ATT&CK: Unknown

Local: No
Remote: Yes

Availability: 🔍
Status: Not defined
Price Prediction: 🔍
Current Price Estimation: 🔍


Threat Intelligenceinfoedit

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍


Recommended: Upgrade
Status: 🔍

0-Day Time: 🔍

Upgrade: Server 2.1.3


02/28/2020 🔍
04/20/2020 +52 days 🔍
04/21/2020 +1 days 🔍
10/10/2020 +172 days 🔍


Advisory: blog.zulip.org
Status: Not defined
Confirmation: 🔍

CVE: CVE-2020-9444 (🔍)
See also: 🔍


Created: 04/21/2020 09:37 AM
Updated: 10/10/2020 05:41 PM
Changes: (1) advisory_confirm_url
Complete: 🔍


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