CVE-2026-40300

EUVD-2026-29537
Zulip is an open-source team collaboration tool. Prior to 12.0, With message_edit_history_visibility_policy set to "moves", /api/v1/messages/{id}/history still returns historical content values, allowing low-privilege users to recover text that was edited away from other users' messages. This vulnerability is fixed in 12.0.
ProviderTypeBase ScoreAtk. VectorAtk. ComplexityPriv. RequiredVector
GitHub_MCNA
6.5 MEDIUM
NETWORK
LOW
LOW
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N
Base Score
CVSS 3.x
EPSS Score
Percentile: 15%
Affected Products (NVD)
VendorProductVersion
zulipzulip_server
10.0
𝑥
= Vulnerable software versions
Early Detection
Affected products identified ahead of NVD analysis through intelligence sources.
VendorProductVersionSource
zulipzulip
𝑥
< 12.0
CNA
Common Weakness Enumeration
References
https://github.com/zulip/zulip/security/advisories/GHSA-jp8f-mvv6-89cr
https://github.com/zulip/zulip/security/advisories/GHSA-jp8f-mvv6-89cr