CVE-2026-97701 (GCVE-0-2026-97701)

Vulnerability from cvelistv5 – Published: 2026-11-04 19:09 – Updated: 2026-11-04 20:31
VLAI
Title
Zulip: Missing content-length limit on POST /messages/render allows denial-of-service via oversized requests
Summary
Zulip is an open-source team collaboration tool. In Zulip Server versions through 12.1, the authenticated POST /messages/render endpoint renders the content parameter without enforcing the normal message length limit used by message send and edit operations. An authenticated user can submit Markdown up to the server body-size limit, causing disproportionate backend CPU consumption, and repeated or concurrent requests can degrade Markdown rendering performance or backend availability for other users. This issue is fixed in version 12.2.
Severity
6.5 (Medium)
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-11-04 20:31 UTC
CWE
  • CWE-770 - Allocation of Resources Without Limits or Throttling
Assigner
GitHub_M CNA
References
Impacted products
Vendor Product Version
zulip zulip Affected: < 12.2
Create a notification for this product.
Show details on NVD website
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