No exploitation reported

CVE-2026-103678

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

No exploitation reported by the sources we read.

Published2026-10-01
WeaknessCWE-125

Am I affected?

With a domain, we read the version its public headers and pages expose. A distribution build can carry the fix under an older number.

Description

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.

Timeline

dates in UTC

2026-10-0112:17CVE publishedNVD

Observed activity

isMalicious corpus · updated 2026-10-23 18:48 UTC

Indicators tagged with this CVE, per day0 indicators over 7 days

Block these indicators

Firewall list (EDL, text): https://api.ismalicious.com/edl/cve/CVE-2026-103678?format=txt
CSV export: https://api.ismalicious.com/edl/cve/CVE-2026-103678?format=csv
TAXII collection of exploited CVEs
The EDL and CSV take an API key on the Pro plan.

Versions per branch

NVD

Tnef project tnef

Branch	Affected	Fixed in	Source
1.4	≤ 1.4.18	no fix published	NVD

as publishedRanges as NVD and OSV publish them; a distribution’s build can be fixed under an older number.

Distribution builds and vendor advisories

Packages from OSV.dev and products from the vendors' CSAF advisories.

version not verifiedVersions not verified: read as OSV.dev and the vendors publish them, not checked against each vendor's release list.

Vendor advisories

CVE-2026-103678 Red Hat Product Security
tnef: Heap out-of-bounds read in get_rtf_data_from_buf() via uncompressed RTF MAPI value

Full record on NVD

Fix

No fix published by the sources we read yet. NVD record

Detection

Nuclei template: none so far
Exploit-DB: no entry
Proof-of-concept repositories: none listed

Sources

CISA-ADPSSVC decisionnone2026-10-01
OpenCVESSVC decisionnone—
CNACVSS 3.15.4read 2026-10-23
NVDCVSS 3.18.1read 2026-10-23
CNAweakness (CWE)CWE-125read 2026-10-23
FIRST EPSSEPSS score0.2 %2026-10-22

Technical details

CVSS v3 Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:H
Published: 2026-10-01
Last Modified: 2026-10-05
NVD status: Analyzed

Frequently asked questions

What is CVE-2026-103678?

Is CVE-2026-103678 actively exploited?

Active exploitation of CVE-2026-103678 has not been confirmed. Its EPSS score was 0.2% on 2026-10-22, the estimated probability of exploitation in the next 30 days.

What is the CVSS score for CVE-2026-103678?

CVE-2026-103678 has a CVSS v3 base score of 8.1 (HIGH severity), with vector string CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:H.

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