Heap Out-of-Bounds Read in ytnef by Yeraze
CVE-2026-111146

6.9MEDIUM

Key Information:

Vendor: Yeraze
Status: Ytnef
Vendor: CVE Published:; 15 October 2026

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👾 Exploit Exists🟡 Public PoC

What is CVE-2026-111146?

The ytnef library version 2.1.2 and earlier contains a heap out-of-bounds read vulnerability within the MAPIPrint() function. Attackers can exploit this vulnerability by providing specially crafted winmail.dat files that contain compressed RTF properties lacking a NUL terminator. This can lead to an over-read during printf operations, potentially causing crashes in ytnefprint and revealing adjacent heap memory contents, which poses a significant security risk.

Affected Version(s)

ytnef 0 <= 2.1.2

Exploit Proof of Concept (PoC)

PoC code is written by security researchers to demonstrate the vulnerability can be exploited. PoC code is also a key component for weaponization which could lead to ransomware.

CVE-2026-111146 - Proof of Concept