{"id":"CVE-2026-52687","state":"PUBLISHED","title":"An attacker that has valid credentials can select a compression algorithm for the IMAP connection whose decompression state requires a large amount of memory, and open several such","description":"An attacker that has valid credentials can select a compression algorithm for the IMAP connection whose decompression state requires a large amount of memory, and open several such connections. The memory limit of the process is reached with only a few connections, terminating the process and all connections it handles, which can cause degradation or denial of service for IMAP. Disable IMAP compression. Alternatively limit the number of connections handled by a single imap-login process, though this has a performance impact. Update to non-vulnerable version. No publicly available exploits are known.","publishedAt":"2026-08-28T10:12:31.701Z","updatedAt":"2026-08-28T15:53:30.084Z","severity":{"score":6.5,"label":"Medium","version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","source":"OX"},"assigner":"OX","products":["Open-Xchange GmbH OX Dovecot Pro","Open-Xchange GmbH OX Dovecot CE"],"affected":[{"vendor":"Open-Xchange GmbH","product":"OX Dovecot Pro","defaultStatus":"unaffected","versions":[{"version":"2.3.11","status":"affected","lessThan":"2.3.22.2","versionType":"semver"},{"version":"3.0.0","status":"affected","lessThan":"3.0.7","versionType":"semver"},{"version":"3.1.0","status":"affected","lessThan":"3.1.6","versionType":"semver"}],"modules":["core"]},{"vendor":"Open-Xchange GmbH","product":"OX Dovecot CE","defaultStatus":"unaffected","versions":[{"version":"2.3.11","status":"affected","lessThan":"2.4.5","versionType":"semver"}],"modules":["core"]}],"references":["https://documentation.open-xchange.com/dovecot/security/advisories/csaf/2026/oxdc-adv-2026-0003.json"],"weaknesses":["CWE-400"],"ingestedAt":"2026-10-29T20:12:16.098Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/52xxx/CVE-2026-52687.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-52687","state":"PUBLISHED","datePublished":"2026-08-28T10:12:31.701Z","dateUpdated":"2026-08-28T15:53:30.084Z","assignerShortName":"OX","assignerOrgId":"8ce71d90-2354-404b-a86e-bec2cc4e6981","dateReserved":"2026-06-08T08:05:31.708Z"},"containers":{"cna":{"descriptions":[{"lang":"en","value":"An attacker that has valid credentials can select a compression algorithm for the IMAP connection whose decompression state requires a large amount of memory, and open several such connections. The memory limit of the process is reached with only a few connections, terminating the process and all connections it handles, which can cause degradation or denial of service for IMAP. Disable IMAP compression. Alternatively limit the number of connections handled by a single imap-login process, though this has a performance impact. Update to non-vulnerable version. No publicly available exploits are known."}],"affected":[{"vendor":"Open-Xchange GmbH","product":"OX Dovecot Pro","defaultStatus":"unaffected","versions":[{"version":"2.3.11","status":"affected","lessThan":"2.3.22.2","versionType":"semver"},{"version":"3.0.0","status":"affected","lessThan":"3.0.7","versionType":"semver"},{"version":"3.1.0","status":"affected","lessThan":"3.1.6","versionType":"semver"}],"modules":["core"]},{"vendor":"Open-Xchange GmbH","product":"OX Dovecot CE","defaultStatus":"unaffected","versions":[{"version":"2.3.11","status":"affected","lessThan":"2.4.5","versionType":"semver"}],"modules":["core"]}],"references":[{"url":"https://documentation.open-xchange.com/dovecot/security/advisories/csaf/2026/oxdc-adv-2026-0003.json","tags":["vendor-advisory"]}],"metrics":[{"cvssV3_1":{"attackComplexity":"LOW","attackVector":"NETWORK","availabilityImpact":"HIGH","baseScore":6.5,"baseSeverity":"MEDIUM","confidentialityImpact":"NONE","integrityImpact":"NONE","privilegesRequired":"LOW","scope":"UNCHANGED","userInteraction":"NONE","vectorString":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","version":"3.1"},"format":"CVSS","scenarios":[{"lang":"en","value":"GENERAL"}]}],"problemTypes":[{"descriptions":[{"cweId":"CWE-400","description":"Uncontrolled Resource Consumption","lang":"en","type":"cwe"}]}],"providerMetadata":{"shortName":"OX","orgId":"8ce71d90-2354-404b-a86e-bec2cc4e6981","dateUpdated":"2026-08-28T10:31:02.454Z"},"source":{"defect":"DOV-9530","discovery":"INTERNAL"}},"adp":[{"title":"CISA ADP Vulnrichment","metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-08-28T14:32:23.865843Z","id":"CVE-2026-52687","options":[{"Exploitation":"none"},{"Automatable":"no"},{"Technical Impact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-08-28T15:53:30.084Z"}}]}}}