CVE-2026-103678

MEDIUM 5.4

Tnef: heap out-of-bounds read in get_rtf_data_from_buf() via uncompressed rtf mapi value

CVSS Score

5.4

EPSS Score

0.0%

EPSS Percentile

0th

A flaw was found in tnef. An attacker can exploit this vulnerability by providing a specially crafted file containing uncompressed Rich Text Format (RTF) data. Because the application fails to properly validate input buffer boundaries before copying data in get_rtf_data_from_buf(), reading beyond the allocated memory occurs. This flaw can cause the application to crash, leading to a Denial of Service (DoS), or leak sensitive memory contents into extracted output files.

CWE	CWE-125
Published	Oct 1, 2026

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CVSS v3 Breakdown

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:L

Attack Vector

Network

Attack Complexity

Low

Privileges Required

None

User Interaction

Required

Scope

Unchanged

Confidentiality

Low

Integrity

None

Availability

Low

References

NVD ↗ CVE.org ↗ EPSS Data ↗

access.redhat.com: https://access.redhat.com/security/cve/CVE-2026-103678 bugzilla.redhat.com: https://bugzilla.redhat.com/show_bug.cgi?id=2544476 github.com: https://github.com/verdammelt/tnef

Credits

Red Hat would like to thank Julien Ahrens (RCE Security GmbH) for reporting this issue.