{"id":"CVE-2026-71263","url":"https://www.cyber-defence.io/tools/cve/CVE-2026-71263","generatedAt":"2026-10-28T03:26:42.533Z","title":"The LINUXTCP port of FreeModbus contains an off-by-one bounds check in xMBPortTCPPool (demo/LINUXTCP/port/porttcp.c).","description":"The LINUXTCP port of FreeModbus contains an off-by-one bounds check in xMBPortTCPPool (demo/LINUXTCP/port/porttcp.c). The check uses a strict greater-than comparison instead of greater-than-or-equal against the 263-byte MB_TCP_BUF_SIZE limit.","published":"2026-08-05T13:24:50.000Z","lastModified":"2026-10-24T15:10:00.000Z","status":"Deferred","sourceIdentifier":"309f9ea4-e3e9-4c6c-b79d-e8eb01244f2c","cvss":{"version":"3.1","score":9.1,"severity":"CRITICAL","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:H"},"cwe":["CWE-787"],"affected":[],"epss":{"score":0.00501,"percentile":0.4263,"date":"2026-10-26","history":[]},"kev":{"listed":false},"exploits":{"count":0,"verified":false,"firstPublished":null,"source":"Exploit-DB (https://gitlab.com/exploit-database/exploitdb)","entries":[]},"verdict":{"level":"high","text":"High impact if exploited, but EPSS currently rates exploitation as unlikely (0.50%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit."},"changes":[],"references":[{"url":"https://github.com/cwalter-at/freemodbus","source":"309f9ea4-e3e9-4c6c-b79d-e8eb01244f2c"},{"url":"https://github.com/cwalter-at/freemodbus/blob/master/demo/LINUXTCP/port/porttcp.c","source":"309f9ea4-e3e9-4c6c-b79d-e8eb01244f2c"}],"sources":{"nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-71263","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."}