{"id":"CVE-2026-103680","url":"https://www.cyber-defence.io/tools/cve/CVE-2026-103680","generatedAt":"2026-10-27T23:59:14.190Z","title":"A heap-based buffer overflow can occur in the find_free_number() function when generating numbered backup suffixes for duplicate filenames.","description":"A flaw was found in tnef. A heap-based buffer overflow can occur in the find_free_number() function when generating numbered backup suffixes for duplicate filenames. When numbered backups are enabled and file overwriting is disabled, an attacker can supply a specially crafted Transport Neutral Encapsulation Format (TNEF) file with an excessive number of colliding attachment filenames, causing the numeric counter to write past the allocated memory buffer. This issue may result in an application crash, leading to a Denial of Service (DoS), or potentially arbitrary code execution.","published":"2026-10-01T12:17:16.000Z","lastModified":"2026-10-05T13:42:11.000Z","status":"Analyzed","sourceIdentifier":"patrick@puiterwijk.org","cvss":{"version":"3.1","score":6.5,"severity":"MEDIUM","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H"},"cwe":["CWE-787"],"affected":["tnef project/tnef"],"epss":{"score":0.00322,"percentile":0.24981,"date":"2026-10-26","history":[{"date":"2026-10-02","score":0.00285,"percentile":0.19097}]},"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 (0.32%). Track it; it rarely justifies an emergency change on its own."},"changes":[{"kind":"scored","label":"Newly scored","at":"2026-10-05T14:30:06.000Z","detail":{"from":"3.1","score":"6.5","severity":"MEDIUM","fromSeverity":"LOW"},"summary":"Now scored CVSS 6.5 MEDIUM (was 3.1)."},{"kind":"new","label":"New CVE","at":"2026-10-01T12:17:16.000Z","detail":{"score":"3.1","severity":"LOW","publishedAt":"2026-10-01T12:17:15.810Z"},"summary":"New CVE, medium severity (CVSS 6.5)."}],"references":[{"url":"https://access.redhat.com/security/cve/CVE-2026-103680","tags":["Third Party Advisory"],"source":"patrick@puiterwijk.org"},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=2544478","tags":["Issue Tracking","Third Party Advisory"],"source":"patrick@puiterwijk.org"},{"url":"https://github.com/verdammelt/tnef","tags":["Product"],"source":"patrick@puiterwijk.org"}],"sources":{"nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-103680","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."}