Out-of-bounds Read in Yeraze Ytnef
CVE-2026-111145
ytnef through 2.1.2 contains a heap out-of-bounds read vulnerability in DecompressRTF() in lib/ytnef.c that never validates uncompressedSize for uncompressed RTF streams. Attackers can supply a crafted winmail.dat TNEF attachment with a malicious PT_BINARY MAPI property to crash ytnefprint or libytnef callers and leak adjacent heap memory.
Vulnerability class: Buffer Overflow
Published .
CVSS v3 metric
CVSS v3 base score 6.1 (Medium). Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:H.
EPSS exploit prediction
No EPSS score from FIRST.org yet. New CVEs usually get one within a few days; no score means no signal yet, not low risk. How EPSS works.
Affected products
Weakness classification (CWE)
References
- hackmd.io/@haind-pwn/ytnef-decompressrtf-oob-read (technical-description, exploit)
- github.com/Yeraze/ytnef/issues/112 (issue-tracking)
- github.com/Yeraze/ytnef/blob/d9f089144414d3b0912c29ab96f8f1c591d00319/lib/ytnef… (technical-description)
- github.com/Yeraze/ytnef (product)
- www.vulncheck.com/advisories/ytnef-through-2.1.2-heap-out-of-bounds-read-via-de… (third-party-advisory)
Frequently asked questions
- What is CVE-2026-111145?
- CVE-2026-111145 is a medium-severity vulnerability in Yeraze Ytnef, classified under Out-of-bounds Read. CVSS score: 6.1/10. Published 2026-10-15.
- How severe is CVE-2026-111145?
- Medium severity. CVSS v3 base score is 6.1 out of 10.