CVE-2023-227354.4MediumCWE-436

CVE-2023-22735: User uploads proxied from S3 lack `Content-Security-Policy` headers, may be served with `Content-Disposition: inline` in zulip

zulip

Vendor fix available · Affected: zulip · Exploitation: unlikely (under 1%)

Not in CyberSIXT coverage yet: no article names this CVE. This page shows the public record.

0.5%probability of exploitation in the next 30 days

44th percentile

050100

Higher than 44% of scored CVEs

4.4MediumCVSS 3.1

LowMediumHighCrit.

DescriptionCVE.org

Zulip is an open-source team collaboration tool. In versions of zulip prior to commit `2f6c5a8` but after commit `04cf68b` users could upload files with arbitrary `Content-Type` which would be served from the Zulip hostname with `Content-Disposition: inline` and no `Content-Security-Policy` header, allowing them to trick other users into executing arbitrary Javascript in the context of the Zulip application. Among other things, this enables session theft. Only deployments which use the S3 storage (not the local-disk storage) are affected, and only deployments which deployed commit 04cf68b45ebb5c03247a0d6453e35ffc175d55da, which has only been in `main`, not any numbered release. Users affected should upgrade from main again to deploy this fix. Switching from S3 storage to the local-disk storage would nominally mitigate this, but is likely more involved than upgrading to the latest `main` which addresses the issue.

Affected products1

From the CVE record. A product or version that is not listed is unknown, not unaffected.

zulip · zulip>= 04cf68b, < 2f6c5a8

On the Atlas

Every published CVE is on the CyberSIXT Atlas, grouped by weakness, vendor and month.

Open the Atlas

Exploitation: Unlikely (under 1%). EPSS under 1%, or no score yet.
CISA KEV: Not listed
Public check: No public nuclei template
Weakness: Interpretation Conflict · Input Validation and Logic
Vendor: zulip
Published: February 2023
Band: Unlikely (under 1%), February 2023

CoverageNo articles yet

No CyberSIXT article names CVE-2023-22735 yet, so there is no coverage timeline, action brief or change log for it. Everything on this page comes from the public CVE record, CISA KEV, EPSS and the nuclei template index. Search the archive or see the CVEs in the news.