CVE-2026-115786
CVE-2026-115786 · Zimbra Collaboration Suite Shared-File Mailbox Quota Accounting Error Enables Quota Exhaustion
This page contains facts from public vulnerability sources. Check the original advisory before updating.
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.
CVSS 6.5 · Medium · EPSS 0.4%
- Published
- Updated
Affected products and versions
zimbra collaboration suite
- Versions
- ≥ 0, ≤ 10.1.20: Affected (semver)
No fix published