Tnef: heap out-of-bounds read in get_rtf_data_from_buf() via uncompressed rtf mapi value (CVE-2026-103678) | HOL Guard CVE

Medium · CVSS 5.4CVE-2026-103678

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

Answer in brief

CVE-2026-103678 records a Medium severity (CVSS 5.4) vulnerability in Tnef: heap out-of-bounds read in get_rtf_data_from_buf() via uncompressed rtf mapi value. The current sources do not mark it as known exploited. The current feed maps tnef (generic). Check affected ranges and fixed versions before updating.

Analysis pending evidence review

HOL Guard separates source facts from reviewed analysis. See the methodology.

Published Oct 1, 2026Updated Oct 1, 2026Source checked Oct 1, 2026First seen by HOL Oct 1, 2026Material review Oct 1, 2026

Upstream Advisory

Key facts

Risk: Medium · CVSS 5.4
Exploitation: Not marked as known exploited
Affected software: 1 mapped package or product
Fix availability: Not reported

Why this deserves its current priority

CVSS is 5.4. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.

Analysis status

Analysis pending evidence review

Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.

Affected scope and exposure questions

The current feed maps tnef (generic). Check affected ranges and fixed versions before updating.

Mapped affected packages and fixed versions
Package	Affected range	Fixed version
tnefgeneric	>=0 <=1.4.18	Not reported

Recommended response

Check inventory. Check lockfiles and deployed manifests for tnef.
Review the reported fix. Monitor this advisory for an available fix and review any installs of the affected package.

Evidence timeline and material changes

Published upstream
Oct 1, 2026
Evidence: source:cvelist:source_dates:source-dates:record
Source modified
Oct 1, 2026
Evidence: source:cvelist:source_dates:source-dates:record
First seen by HOL
Oct 1, 2026

Sources and claim methodology

Upstream source 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.

Quoted source text, attributed separately from HOL analysis.