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TI-2026-74929 Aliases CVE-2026-111145

Heap out-of-bounds read in ytnef RTF decompression

Priority MEDIUM 64CWE-125Published · Updated

Key facts

Attack vector
Local
Privileges required
None
User interaction
Passive
Attack complexity
Low
Attack requirements
None
Impact type
—
Confidentiality · integrity · availability
Low · None · High
Fix status
No fix listed

Attack profile from CVSS 4.0 · CNA. Fix status from CNA.

Summary

ytnef through 2.1.2 contains a heap out-of-bounds read in DecompressRTF() in lib/ytnef.c, which never validates uncompressedSize for uncompressed RTF streams (CWE-125). 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. A public exploit is linked in the references.

Written with Claude Haiku 5.5 from the sources below · 2026-10-28

Description from the CNA

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.

Why it matters now

Exploitation Proof of concept CISA SSVC · not in CISA KEV
EPSS 0.00127 2nd percentileScored 2026-11-07
Public exploit Yes 1 exploit referenceTagged by the CNA
Fix No fix listed No fixed version in the sources yet

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
Poc
Automatable
No
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
Yerazeytnefup to 2.1.2—No fix listedCNA
  • ytnef VendorYeraze Affected up to 2.1.2 Fixed in — No fix listed CNA

Remediation

The sources list no fixed version for ytnef.

Written with Claude Haiku 5.5 from the sources below · 2026-10-28

Timeline

  1. 2026-10-16 Threatist record created from CVE-2026-111145
  2. 2026-10-16 Priority changed: MEDIUM → LOW
  3. 2026-10-21 CISA SSVC decision points changed
  4. 2026-10-21 Priority changed: LOW → MEDIUM

References

Exploit 1

Other 3

  • TI-2026-74930 Heap out-of-bounds read in ytnef MAPIPrint leaks memory CVSS 4.0MEDIUM 6.9

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences