CVE-2026-55781
LOW
INFO
Priority: 0.00
BB Relevance:
20/100
Published: 2026-07-10
Modified: 2026-10-25
First seen: 2026-10-29
Status: active
Attack Surface
Low Complexity
CVSS Vector Breakdown
AV:
Local
AC:
Low
PR:
Low
UI:
Passive
S:
X
AT:
None
VC:
None
VI:
None
VA:
Low
Description
NanaZip is the 7-Zip derivative intended for the modern Windows experience. Prior to 6.5.1749.0, NanaZip's UFS and FFS image handler in NanaZip.Codecs.Archive.Ufs.cpp validates the superblock block size only against the MINBSIZE lower bound and does not validate the fs_fsize fragment size, allowing attacker-controlled 32-bit fields to flow into indirect-block, directory, and extraction buffer allocations. A tiny crafted UFS image can force multi-gigabyte allocations during open or extraction, causing memory exhaustion or process termination. This issue is fixed in version 6.5.1749.0.