CVE-2019-16215 json
The Markdown parser in Zulip server before 2.0.5 used a regular expression vulnerable to exponential backtracking.
published 2019-09-18 7 y ago modified 2026-06-17 4 mo ago also EUVD-2019-7027
- cvss
- 6.5
- version 3.1, NVD
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 1.2%
- EPSS 1.2% chance of exploitation in 30 days, percentile 69%
- public exploits
- 0
- none known
Summary
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.
Patch / fix
Exploit prediction
1.25% chance of exploitation in the next 30 days, higher than 69% of all scored CVEs (FIRST EPSS, 2026-11-08).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| NVD | 3.1 | 6.5 | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H |
| NVD | 2.0 | 4.0 | AV:N/AC:L/Au:S/C:N/I:N/A:P |
Classification
- Weakness
-
- CWE-1333 Inefficient Regular Expression Complexity
References
-
github.com
/zulip/zulip/commit/5797f013b3be450c146a4141514bda525f2f1b51
patch, third-party-advisory
-
blog.zulip.org
/2019/09/11/zulip-server-2-0-5-security-release/
vendor-advisory
Sources
- CVE List CVE-2019-16215
- NVD CVE-2019-16215
Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.