CVE-2019-16216
lowpriority · track · 22EPSS 0.007 · 52 %ileEUUSEPSS · scored 2026-10-27
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.
cvss
Technical severity, 0–10. One row per scoring source.
base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · low–medium · 3.5–5.4
weaknesses
The CWE weakness classes this flaw belongs to.
affected products (2)
Products and version ranges known to be affected.
also known as (3)
Other names and identifiers for this entity.
sources
Which sources assert this record, and when.
references (7)
External citations — patches, advisories, analysis.
- https://blog.zulip.org/2019/09/11/zulip-server-2-0-5-security-release/cnnvd
- https://github.com/zulip/zulip/commit/1195841dfb9aa26b3b0dabc6f05d72e4af25be3ecnnvd
- https://nvd.nist.gov/vuln/detail/CVE-2019-16216cnnvd
- https://blog.zulip.org/2019/09/11/zulip-server-2-0-5-security-release/enisa_euvd
- https://github.com/zulip/zulip/commit/1195841dfb9aa26b3b0dabc6f05d72e4af25be3eenisa_euvd
- https://blog.zulip.org/2019/09/11/zulip-server-2-0-5-security-release/Vendor Advisorynvd
- https://github.com/zulip/zulip/commit/1195841dfb9aa26b3b0dabc6f05d72e4af25be3ePatchThird Party Advisorynvd
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