NanaZip's UFS and FFS image handler performs insufficient validation of the superblock block size (fs_bsize) and ignores the fragment size (fs_fsize). A malicious 32‑bit value in a crafted UFS image can cause the program to allocate indirect‑block, directory, or extraction buffers of multi‑gigabyte size, leading to memory exhaustion or process termination. This vulnerability results in a denial‑of‑service condition without compromising data confidentiality or integrity.

Users of the M2Team NanaZip application running any release earlier than version 6.5.1749.0 are affected. The flaw resides in the NanaZip.Codecs.Archive.Ufs component used for opening or extracting UFS or FFS images.

The CVSS score of 2.4 indicates low severity, and the EPSS score of less than 1% suggests that exploitation is unlikely. The vulnerability is not listed in the CISA KEV catalog, further reducing the likelihood of widespread attacks. An adversary can trigger the issue by providing a maliciously crafted UFS image to the application; the attack requires the ability to influence a file NanaZip processes.