Vulnerability · Published Jun 12, 2026 · Assigned by GitHub_M

CVE-2026-47223NanaZip: Heap out-of-bounds read in NanaZip AVB hashtree descriptor parser via 32-bit unsigned integer overflow

Medium 5.4

In plain English

A medium-severity out-of-bounds read in NanaZip from M2Team. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.2% (higher than 13% of all known vulnerabilities).

Severity (CVSS 3.1)5.4Medium
Exploit odds (30 days)0.2%top 87.2% of all CVEs
Exploited in the wildNo reportsCISA SSVC: poc
Attack toolingNoneno public tooling known

Official description

NanaZip is the 7-Zip derivative intended for the modern Windows experience. From version 3.0.1000.0 to before version 6.0.1698.0, a heap out-of-bounds read exists in the Android Verified Boot (AVB) vbmeta image parser in NanaZip (via the upstream 7-Zip AvbHandler). A 32-bit unsigned integer overflow in the bounds check pos + ht.salt_len > descSize allows an attacker-controlled salt_len field to bypass validation, causing CByteBuffer::CopyFrom to memcpy up to ~4 GiB past the end of a 64. This issue has been patched in stable version 6.0.1698.0 and preview version 6.5.1742.0.

Affected products (as reported)

VendorProductVersions
M2Team NanaZip >= 3.0.1000.0, < 6.0.1698.0

Weakness: CWE-125, CWE-190 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:L

References