Zulip Server
CVE-2017-0896
MEDIUM
Vulnerability Assessment
| Weakness |
CWE
OWASP Top 10:2025
A01:2025 - Broken Access Control
ASVS 5.0
V8 - Authorization Authorization verification
MITRE ATT&CK
1 technique across 1 tactic: Defense Evasion The technique list with ATT&CK links and the kill-chain view is part of the Basic plan and up. |
| Impact | CVSS score of 6.5 (MEDIUM). Attack characteristics: network attack vector, low complexity, low privileges required, no user interaction not required. EPSS exploitation probability: 0.15%. |
| Exploit ScenarioDerived | This vulnerability can be exploited remotely over the network. Successful exploitation could compromise the medium-severity affected system. |
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Alert meAnalysisAI
Zulip Server 1.5.1 and below suffer from an error in the implementation of the invite_by_admins_only setting in the Zulip group chat application server that allowed an authenticated user to invite. Rated medium severity (CVSS 6.5), this vulnerability is remotely exploitable, low attack complexity.
RemediationAI
A vendor patch is available. Apply the latest security update as soon as possible. Apply vendor patches when available. Implement network segmentation and monitoring as interim mitigations.
Affects your stack
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Checking this CVE against your own stacks and servers is part of the Basic plan and up.
Technical ContextAI · show details
This vulnerability is classified under CWE-285. Zulip Server 1.5.1 and below suffer from an error in the implementation of the invite_by_admins_only setting in the Zulip group chat application server that allowed an authenticated user to invite other users to join a Zulip organization even if the organization was configured to prevent this. Affected products include: Zulip Zulip Server.
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- Exploit and PoC references, threat intelligence from 22 sources
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Severity by source
AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N
Primary rating from NVD · only source for this CVE.
CVSS VectorNVD
DescriptionCVE.org
Zulip Server 1.5.1 and below suffer from an error in the implementation of the invite_by_admins_only setting in the Zulip group chat application server that allowed an authenticated user to invite other users to join a Zulip organization even if the organization was configured to prevent this.
Threat Intelligence Overview
NVD
CVE.org
EPSS
GitHub
How this decision was reached
The engine reads each signal below and applies a fixed list of rules from top to bottom. The first rule that matches sets the recommended action – like a statement, every line is shown.
What every action level means
SSVC AssessmentENISA
Priority Score
Attack Technique
Authentication bypass attacks exploit flaws in the verification mechanisms that control access to systems and applications.
Affected Products (CPE)CVE.org
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