Dashboard / CVE-2026-100404

CVE-2026-100404

MEDIUM
MEDIUM Priority: 0.03 BB Relevance: 63/100
Published: 2026-10-14 Modified: 2026-10-29 First seen: 2026-10-29 Status: active

Attack Surface

Network Low Complexity No Interaction Conf. Impact

CVSS Vector Breakdown

AV: Network
AC: Low
PR: Low
UI: None
S: Unchanged
C: High
I: None
A: None

Description

Zulip is an open-source team collaboration tool. In Zulip Server versions through 12.1, guest users can receive new message events for public channels outside their subscriptions. A guest can trigger the issue by registering an event queue with parameters that request messages from an unsubscribed public channel, or an existing event queue can remain affected after the guest's access to the channel is removed. The flaw discloses new public-channel messages to the guest. This issue is fixed in version 12.2.

Weakness Classification (1)

Affected Software (1)

VendorProductVersion
zulip zulip < 12.2

References & Advisories (5)

Bug Bounty Relevance

63 / 100
✓ Network accessible
✓ Low complexity
✓ No user interaction

CVSS Score

6.5 / 10.0 v3.1
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N

EPSS — Exploitation Probability

0.41%
Raw Score 0.004150
Percentile 35.8%
Date 2026-10-29

EPSS Trend

2026-10-29
0.00415
2026-10-28
0.00415

Intelligence Sources

mitre ref →
nvd ref →

External Links