CVE-2026-97701
mediumZulip is an open-source team collaboration tool.
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.
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H Affected products
Not reported by the source (unknown — not "none").
Weakness classification (CWE)
Source: NVD / CISA. “NVD-CWE-Other” and “NVD-CWE-noinfo” mean NVD could not assign a specific weakness.
Mitigation & advisories
No vendor advisory or patch reference tagged by NVD. Check the references below.
References
- https://github.com/zulip/zulip/commit/31773c77c501391ede0fa8ec727f39508664e0ae security-advisories@github.com
- https://github.com/zulip/zulip/commit/4d94dd2ee6337a4b3351694dd314a45d3fe11031 security-advisories@github.com
- https://github.com/zulip/zulip/pull/39913 security-advisories@github.com
- https://github.com/zulip/zulip/releases/tag/12.2 security-advisories@github.com
- https://github.com/zulip/zulip/security/advisories/GHSA-m257-w4r5-5rmf security-advisories@github.com
- https://zulip.readthedocs.io/en/latest/overview/changelog.html#zulip-server-12-2 security-advisories@github.com