{"id":"CVE-2026-103010","revision":"089945b380024c3aa4bd41f484b9fac1","records":[{"revision":"089945b380024c3aa4bd41f484b9fac1","observedAt":"2026-10-23T15:48:27.903+00:00","statement":{"source":"cve-program","id":"CVE-2026-103010","aliases":[],"title":"Heap-based Buffer Overflow in hMailServer","description":"Heap-based buffer overflow in the legacy Blowfish decryption routine (BlowFishEncryptor::DecryptFromString) in Progressive Robot hMailServer 6.0.0 through 6.3.3 on Windows allows a local interactive user with no hMailServer credentials to write bytes of their choosing past the end of a 255-byte heap buffer in the hMailServer service process, which runs as LocalSystem by default. The user does this by passing a long hexadecimal string to the COM method Utilities.BlowfishDecrypt, which checked no authentication. The routine converted hexadecimal input of any length into a fixed 255-byte buffer before decrypting it in place. The result is a denial of service (service crash), and possibly code execution with the privileges of the service account.","state":0,"publishedAt":"2026-10-08T10:53:10.627+00:00","modifiedAt":"2026-10-08T14:22:28.966+00:00","affected":[{"ecosystem":"Vendor product","name":"hMailServer","ranges":[],"versions":[],"rawVersionEvidence":"{\n                    \"vendor\": \"Progressive Robot Ltd\",\n                    \"product\": \"hMailServer\",\n                    \"repo\": \"https://gitlab.com/hmailserver/hmailserver\",\n                    \"versions\": [\n                        {\n                            \"version\": \"6.0.0\",\n                            \"status\": \"affected\",\n                            \"lessThan\": \"6.3.4\",\n                            \"versionType\": \"semver\"\n                        }\n                    ],\n                    \"defaultStatus\": \"unaffected\"\n                }"}],"metrics":[{"system":"CVSS 3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","score":7.8,"severity":"HIGH"}],"references":["https://gitlab.com/hmailserver/hmailserver/-/commit/135a1908ff820ed587d5f180f98c53bd010d8931","https://gitlab.com/hmailserver/hmailserver/-/releases/v6.3.4","https://gitlab.com/hmailserver/hmailserver/-/work_items/49"],"sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-103010","license":"CVE Program Terms of Use","key":"cve-program:CVE-2026-103010","identifiers":["CVE-2026-103010"]},"retained":false,"historicalAffected":[]}],"coverage":[]}