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OpenAdvisories
Medium · 4.3 CVE-2021-32707 EUVD-2021-19503

Bypass of image blocking in Nextcloud Mail

Published Jul 12, 2021 · Updated Aug 3, 2024 · Assigned by GitHub_M

Description

Nextcloud Mail is a mail app for Nextcloud. In versions prior to 1.9.6, the Nextcloud Mail application does not, by default, render images in emails to not leak the read state. The privacy filter failed to filter images with a `background-image` CSS attribute. Note that the images were still passed through the Nextcloud image proxy, and thus there was no IP leakage. The issue was patched in version 1.9.6 and 1.10.0. No workarounds are known to exist.

Affected products

VendorProductAffectedFixed
nextcloud security-advisories < 1.9.6 —

References