A vulnerability, which was classified as problematic, was found in Zulip Server up to 2.0.4. Affected is an unknown function of the component Markdown Parser. The manipulation as part of a Message leads to a resource consumption vulnerability. CWE is classifying the issue as CWE-400. The product does not properly control the allocation and maintenance of a limited resource, thereby enabling an actor to influence the amount of resources consumed, eventually leading to the exhaustion of available resources. This is going to have an impact on availability. CVE summarizes:

The Markdown parser in Zulip server before 2.0.5 used a regular expression vulnerable to exponential backtracking. A user who is logged into the server could send a crafted message causing the server to spend an effectively arbitrary amount of CPU time and stall the processing of future messages.

The weakness was published 09/18/2019 (Website). The advisory is shared for download at blog.zulip.org. This vulnerability is traded as CVE-2019-16215 since 09/11/2019. The exploitability is told to be easy. It is possible to launch the attack remotely. The successful exploitation requires a authentication. There are neither technical details nor an exploit publicly available. The MITRE ATT&CK project declares the attack technique as T1499.

Upgrading to version 2.0.5 eliminates this vulnerability.

Similar entry is available at VDB-141961.

Productinfo

Vendor

• Zulip

Name

• Server

Version

• 2.0.0
• 2.0.1
• 2.0.2
• 2.0.3
• 2.0.4

License

• open-source

CPE 2.3info

• 🔍
• 🔍
• 🔍

CPE 2.2info

• 🔍
• 🔍
• 🔍

CVSSv4info

CVSSv3info

CVSSv2info

Exploitinginfo

Threat Intelligenceinfo

Countermeasuresinfo

Timelineinfo

Sourcesinfo

Entryinfo

Discussion