Read the docs
TI-2026-30733 Aliases CVE-2026-42444

NanaZip: Unbounded resource consumption in NanaZip littlefs parser via attacker-controlled BlockCount

Priority MEDIUM 58CWE-770Published · Updated

Key facts

Attack vector
Local
Privileges required
None
User interaction
Required
Attack complexity
Low
Impact type
Denial of service
Confidentiality · integrity · availability
None · None · High
Fix status
Fixed

Attack profile from CVSS 3.1 · NVD. Fix status from CNA. Impact type from CWE-770.

Summary

NanaZip is an open source file archive. From 5.0.1252.0 to before 6.0.1698.0, a denial-of-service vulnerability exists in the littlefs filesystem image parser in NanaZip. The handler's Open method reads BlockCount directly from the attacker-controlled superblock without any validation against the actual file size or any upper-bound ceiling, then iterates BlockCount times, allocating a file-path entry per iteration. A crafted 44-byte littlefs image with BlockCount = 0xFFFFFFFF causes ~4 billion heap allocations, exhausting available memory. This vulnerability is fixed in 6.0.1698.0.

Why it matters now

Exploitation Proof of concept CISA SSVC · not in CISA KEV
EPSS 0.00111 1st percentileScored 2026-11-07
Fix Fixed NanaZip (M2Team): 6.0.1698.0

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
M2TeamNanaZip5.0.1250.0 to before 6.0.1698.06.0.1698.0Patch availableCNA
  • NanaZip VendorM2Team Affected 5.0.1250.0 to before 6.0.1698.0 Fixed in 6.0.1698.0 Patch available CNA

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:m2team:nanazip:*:*:*:*:*:*:*:*5.0.1252.0 to before 6.0.1698.0VulnerableM2Team
  • cpe:2.3:a:m2team:nanazip:*:*:*:*:*:*:*:* Versions 5.0.1252.0 to before 6.0.1698.0 Vulnerable ·M2Team

Remediation

  • Fix · CNA NanaZip (M2Team) Fixed in 6.0.1698.0

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-42444

References

Advisory 1

  • TI-2026-32194 NanaZip: Heap out-of-bounds write in NanaZip UFS directory parser CVSS 3.1HIGH 7.1
  • TI-2026-21251 NanaZip has DotNet Single file OOB Heap Read CVSS 4.0MEDIUM 5.2
  • TI-2026-22087 NanaZip UFS Archive Parser Memory Corruption via Unvalidated Directory Record Length CVSS 4.0MEDIUM 5.1
  • TI-2026-22086 NanaZip .NET Single-File Parser Integer Underflow Leads to Unbounded Allocation (DoS) CVSS 4.0MEDIUM 5.1
  • TI-2026-22085 NanaZip .NET Single-File Manifest Parser Vulnerable to Out-of-Bounds Read via Unchecked RelativePathLength CVSS 4.0MEDIUM 5.1
  • TI-2026-21566 NanaZip has ROMFS Archive Infinite Loop CVSS 4.0MEDIUM 5.1
See all 12 →

Sources

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