CVE-2019-16216

Zulip server before 2.0.5 incompletely validated the MIME types of uploaded files. A user who is logged into the server could upload files of certain types to mount a stored cross-site scripting attack on other logged-in users. On a Zulip server using the default local uploads backend, the attack is only effective against browsers lacking support for Content-Security-Policy such as Internet Explorer 11. On a Zulip server using the S3 uploads backend, the attack is confined to the origin of the configured S3 uploads hostname and cannot reach the Zulip server itself.

• CVE ID
• CVE-2019-16216

• Assigner
• cve@mitre.org

• Vulnerability Status
• Analyzed

• Published Version
• 2019-09-18T12:15:10

• Last Modified Date
• 2019-09-18T18:43:07

• Version
• 2.0

• Vector String
• AV:N/AC:M/Au:S/C:N/I:P/A:N

• Access Vector
• NETWORK

• Access Compatibility
• MEDIUM

• Authentication
• SINGLE

• Confidentiality Impact
• NONE

• Integrity Impact
• PARTIAL

• Availability Impact
• NONE

• Base Score
• 3.5

• Severity
• LOW

• Exploitability Score
• 6.8

• Impact Score
• 2.9

• Version
• 3.1

• Vector String
• CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N

• Attack Vector
• NETWORK

• Attack Compatibility
• LOW

• Privileges Required
• LOW

• User Interaction
• REQUIRED

• Scope
• CHANGED

• Confidentiality Impact
• LOW

• Availability Impact
• NONE

• Base Score
• 5.4

• Base Severity
• MEDIUM

• Exploitability Score
• 2.3

• Impact Score
• 2.7