CVE-2019-16216

Description

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.

Category

5.4
CVSS
Severity: Medium
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.30%
Vendor Advisory zulip.org
Affected: n/a n/a
Published at:
Updated at:

References

Link Tags
https://blog.zulip.org/2019/09/11/zulip-server-2-0-5-security-release/ vendor advisory
https://github.com/zulip/zulip/commit/1195841dfb9aa26b3b0dabc6f05d72e4af25be3e third party advisory patch

Frequently Asked Questions

What is the severity of CVE-2019-16216?
CVE-2019-16216 has been scored as a medium severity vulnerability.
How to fix CVE-2019-16216?
To fix CVE-2019-16216, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2019-16216 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2019-16216 is being actively exploited. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
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