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.
Affected products
tnef_project: tnef
References3
- access.redhat.com/security/cve/CVE-2026-103680 Third Party Advisory
- bugzilla.redhat.com/show_bug.cgi?id=2544478 Issue TrackingThird Party Advisory
- github.com/verdammelt/tnef Product
Metrics
- CVSS 3.1
-
6.5
MEDIUM
Score source: NVD
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H - EPSS — exploit probability
- 0% percentile: 25 · as of 10 November 2026
- CWE
- CWE-787
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