Description
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.
References (2)
Core 2
Core References
Vendor Advisory x_refsource_confirm
https://blog.zulip.org/2019/09/11/zulip-server-2-0-5-security-release/
Patch, Third Party Advisory x_refsource_confirm
https://github.com/zulip/zulip/commit/5797f013b3be450c146a4141514bda525f2f1b51
Scores
CVSS v3
6.5
EPSS
0.0049
EPSS Percentile
65.5%
Attack Vector
NETWORK
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Details
CWE
CWE-1333
Status
published
Products (1)
zulip/zulip_server
< 2.0.5
Published
Sep 18, 2019
Tracked Since
Feb 18, 2026