{"id":"CVE-2026-115786","revision":"53c5deda0fae4d5e9e2882a5d9b00a63","records":[{"revision":"53c5deda0fae4d5e9e2882a5d9b00a63","observedAt":"2026-10-28T20:55:13.289+00:00","statement":{"source":"cve-program","id":"CVE-2026-115786","aliases":[],"title":"Zimbra Collaboration Suite Shared-File Mailbox Quota Accounting Error Enables Quota Exhaustion","description":"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.","state":0,"publishedAt":"2026-10-23T13:53:33.918+00:00","modifiedAt":"2026-10-28T19:48:38.75+00:00","affected":[{"ecosystem":"Vendor product","name":"Zimbra Collaboration Suite","ranges":[],"versions":[],"rawVersionEvidence":"{\n                    \"vendor\": \"Zimbra\",\n                    \"product\": \"Zimbra Collaboration Suite\",\n                    \"versions\": [\n                        {\n                            \"status\": \"affected\",\n                            \"version\": \"0\",\n                            \"lessThanOrEqual\": \"10.1.20\",\n                            \"versionType\": \"semver\"\n                        }\n                    ],\n                    \"defaultStatus\": \"unaffected\"\n                }"}],"metrics":[{"system":"CVSS 3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","score":6.5,"severity":"MEDIUM"}],"references":["https://wiki.zimbra.com/wiki/Zimbra_Security_Advisories","https://www.rapid7.com/blog/post/ve-breaking-zimbra-identity-boundaries-part-1/"],"sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-115786","license":"CVE Program Terms of Use","key":"cve-program:CVE-2026-115786","identifiers":["CVE-2026-115786"]},"retained":false,"historicalAffected":[]}],"coverage":[]}