November 14, 2026

CVE Watchtower

CVE-2026-55781M2Team NanaZip Uncontrolled Resource Consumption

NVD

Vulnerability Summary

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.
Severity Level
UNKNOWN
Published Date
Jul 10, 2026
Last Modified
Jul 10, 2026
Exploitation Status
No confirmed exploitation yet
EPSS Score (30-Day)
0.11%Probability
Root Weakness (CWE)
CWE-400: Uncontrolled Resource Consumption β†—
The product does not properly control the allocation and maintenance of a limited resource, enabling denial-of-service conditions.
CWE-789 β†—
See the MITRE CWE entry for the full definition of this weakness.
CVSS v4.0 Base Metrics — Score 2.4 (LOW)
CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:P/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N
Attack VectorLocal
Attack ComplexityLow
Attack RequirementsNone
Privileges RequiredLow
User InteractionPassive
Confidentiality (Vulnerable System)None
Integrity (Vulnerable System)None
Availability (Vulnerable System)Low
Confidentiality (Subsequent System)None
Integrity (Subsequent System)None
Availability (Subsequent System)None

Affected & Patched Versions

Affected Versions
  • M2Team NanaZip < 6.5.1749.0
Patched Versions
No patched version published yet
Until a fix ships, reduce exposure:
  • Restrict access to the affected service or interface to trusted networks.
  • Disable the affected feature if you do not need it.
  • Watch the vendor advisory for a firmware or software update.

What to do

Fix it during your normal patch cycle. No exploitation is confirmed yet.

  1. Check whether you run M2Team NanaZip and which version.
  2. No patched version is listed yet. Limit access to the affected service to trusted networks, and disable the feature if you can.
  3. Subscribe to the vendor advisory so you learn when a fix ships.

Timeline

  • Jul 10, 2026Published
  • Jul 10, 2026Record last modified

Score, severity and exploitation changes are tracked from the day Watchtower started logging them.

Get notified about new M2Team NanaZip CVEsYou are reading CVE-2026-55781. Get an email when KEV listings, exploits or new CVEs match your stack.
Set up CVE alerts

External References

Data last checked: Nov 14, 2026 01:09 UTC