Tnef: heap buffer overflow in find_free_number() via numbered-backup suffix generation
Published Oct 1, 2026
3.1
LOWCVSS 3.1
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
No data.
No data.
No data.
No Red Hat product state for this CVE.
No package ranges for this CVE.
Remediation
No remediation recorded yet.
Metrics
No CVSS v4.0 score for this CVE.
CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:N/I:N/A:L
No CVSS v3.0 score for this CVE.
No CVSS v2.0 score for this CVE.
This CVE is not in the KEV list.
CISA SSVC (Vulnrichment)
Stakeholder-Specific Vulnerability Categorization from CISA ADP.
Exploitation
NoneAutomatable
NoTechnical Impact
PartialDecision
n/aAssessed Oct 1, 2026 · SSVC 2.0.3
No EPSS score for this CVE.
References (3)
- https://access.redhat.com/security/cve/CVE-2026-103680 vdb-entryx_refsource_REDHAT
- https://bugzilla.redhat.com/show_bug.cgi?id=2544478 issue-trackingx_refsource_REDHAT
- https://github.com/verdammelt/tnef
| Link | Providers | Tags |
|---|---|---|
| https://access.redhat.com/security/cve/CVE-2026-103680 | vdb-entryx_refsource_REDHAT | |
| https://bugzilla.redhat.com/show_bug.cgi?id=2544478 | issue-trackingx_refsource_REDHAT | |
| https://github.com/verdammelt/tnef |
Change history (0)
No recorded changes yet.