CVE-2022-31017 — Zulip is an open-source team collaboration tool

Zulip is an open-source team collaboration tool. Versions 2.1.0 through and including 5.2 are vulnerable to a logic error. A stream configured as private with protected history, where new subscribers should not be allowed to see messages sent before they were subscribed, when edi

01What is this vulnerability?

Zulip is an open-source team collaboration tool. Versions 2.1.0 through and including 5.2 are vulnerable to a logic error. A stream configured as private with protected history, where new subscribers should not be allowed to see messages sent before they were subscribed, when edited causes the server to incorrectly send an API event that includes the edited message to all of the stream’s current…

02Affected products

Vendor	Product	Versions
zulip	zulip	>= 2.1.0, < 5.3

03Active exploitation status

Not currently listed on the CISA Known Exploited Vulnerabilities (KEV) catalog. EPSS is the best forward-looking signal — see the EPSS row above.

04Recommended remediation

• Patch to a fixed version listed in the vendor advisory (see references below).
• Mitigate with WAF rules, network egress filters, or feature flags where the patch is not yet available.
• Hunt historical logs for exploitation indicators — see Detection signatures below.

05Technical details

For the full vendor write-up, exploit chains, and reference implementations, see the references list in section 09.

06Detection signatures

Ask SARA in chat to draft a starting detection for this CVE in your stack of choice.

07Related CVEs

No directly-cited follow-up CVEs in the KB record for this advisory. The references list in section 09 carries the vendor cross-references.

08Timeline

• Published: 2022-06-25T08:15:16.000Z
• Last modified: 2025-04-23T18:08:41.319Z

09References

• github.com — https://github.com/zulip/zulip/security/advisories/GHSA-m5j3-jp59-6f3q