Live › vulnerability › CVE-2026-115786
Go to dashboardA logged-in Zimbra Collaboration Suite user can repeatedly share and revoke a document so that the mailbox-wide quota charge is never reversed, filling a recipient's quota. Once the quota is full, the victim cannot receive new mail or perform other size-increasing operations, without any action from the victim.
Summary written from the sources below. Check the originals before acting.
First seen by InfraStack 2026-10-23 21:57 UTC. All times on this page are UTC.
Zimbra Collaboration Suite deployments on the affected versions where accounts have finite quotas and users can share documents with each other. Deployments on other versions, or with unlimited quotas, are less exposed; the sources do not say whether the fix is in a specific build.
No product ranges from the sources yet.
su - zimbra -c "zmcontrol -v"); the sources name 10.1.16 and 10.1.20 as affected.Each row is the first time that source carried this signal. The analyst’s rows are its own findings.
A mailbox quota-accounting vulnerability in Zimbra Collaboration Suite (ZCS) allows an authenticated user to consume another user’s mailbox quota by repeatedly sharing and revoking a document. Creation of the recipient’s shared-file record charges the document size to mailbox-wide usage. Revocation deletes the record and reverses its folder counters without reversing the mailbox-wide charge. Repeated normal share notifications therefore accumulate quota usage after the visible records are gone. On accounts with a finite quota, this can prevent incoming mail and other size-increasing operations without recipient interaction. The issue affects ZCS 10.1.16 and 10.1.20.
This page as .md · .json · in your agent: get_signal("CVE-2026-115786")
NVD data is provided by NIST and is public domain · EPSS scores by FIRST, used with attribution. Posts quoted belong to their authors.