NanaZip: Null-pointer dereference in NanaZip UFS parser when root inode is a symlink

Description

NanaZip is an open source file archive. From 5.0.1252.0 to before 6.0.1698.0, a null-pointer dereference exists in the UFS/UFS2 filesystem image parser in NanaZip. The vulnerability is triggered when opening a crafted UFS image where the root inode (inode 2) is set to IFLNK (symlink) instead of IFDIR (directory). The parser unconditionally treats the root inode as a directory without checking its type, and when the symlink has an embedded target (small di_size), the directory data buffer is zero-length, causing a null-pointer dereference on the first read. This vulnerability is fixed in 6.0.1698.0.

Scores

EPSS (exploitation in 30 days)

0.11% · top 99% of all CVEs (6 Nov 2026)

CISA SSVC

Exploitation: none · Automatable: no · Technical impact: partial

The list uses the assigner's score when there is one, then CISA's, then NVD's: Low 3.3.

Weakness

• CWE-476: NULL Pointer Dereference (opens in a new tab)All about CWE-476 and its CVEs

Affected products

• M2Team · NanaZip

  • affected >= 5.0.1250.0, < 6.0.1698.0

References (1)

• https://github.com/M2Team/NanaZip/security/advisories/GHSA-8r4x-fx3w-ph77 (opens in a new tab)x_refsource_CONFIRM

Sources

The same CVE in the primary databases and aggregators, to check against.

• CVE.org record (opens in a new tab)
• CVE List JSON (GitHub) (opens in a new tab)
• NVD (opens in a new tab)
• FIRST EPSS (opens in a new tab)
• OSV.dev (opens in a new tab)
• GitHub Advisories (opens in a new tab)
• CIRCL Vulnerability-Lookup (opens in a new tab)

Badge for a README or a ticket

[![CVE-2026-42442](https://trackcve.app/badge/CVE-2026-42442.svg)](https://trackcve.app/cve/CVE-2026-42442)

Record last updated 13 May 2026, 14:43 UTC.