{"id":"CVE-2026-115786","url":"https://www.cyber-defence.io/tools/cve/CVE-2026-115786","generatedAt":"2026-10-27T23:50:48.284Z","title":"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.","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.","published":"2026-10-23T14:17:53.000Z","lastModified":"2026-10-23T16:44:18.000Z","status":"Awaiting Analysis","sourceIdentifier":"cve@rapid7.com","cvss":{"version":"3.1","score":6.5,"severity":"MEDIUM","vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H"},"cwe":["CWE-682"],"affected":[],"epss":{"score":0.00374,"percentile":0.31165,"date":"2026-10-26","history":[{"date":"2026-10-24","score":0.00436,"percentile":0.36841}]},"kev":{"listed":false},"exploits":{"count":0,"verified":false,"firstPublished":null,"source":"Exploit-DB (https://gitlab.com/exploit-database/exploitdb)","entries":[]},"verdict":{"level":"low","text":"Lower severity and a low EPSS score (0.37%). Track it; it rarely justifies an emergency change on its own."},"changes":[{"kind":"new","label":"New CVE","at":"2026-10-23T14:17:53.000Z","detail":{"score":"6.5","severity":"MEDIUM","publishedAt":"2026-10-23T14:17:52.867Z"},"summary":"New CVE, medium severity (CVSS 6.5)."}],"references":[{"url":"https://wiki.zimbra.com/wiki/Zimbra_Security_Advisories","source":"cve@rapid7.com"},{"url":"https://www.rapid7.com/blog/post/ve-breaking-zimbra-identity-boundaries-part-1/","source":"cve@rapid7.com"}],"sources":{"nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-115786","epss":"https://www.first.org/epss/","kev":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog","exploitdb":"https://www.exploit-db.com/"},"licence":"CC BY 4.0 — link back to the CVE Explorer if you publish the results; upstream data remains subject to its own terms."}