CVE-2026-47223: NanaZip: Heap out-of-bounds read in NanaZip AVB hashtree descriptor parser via 32-bit unsigned integer overflow
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.saltlen > descSize allows an attacker-controlled saltlen 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 Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
Upgrade
NanaZipto a version that resolves this vulnerability.Fixed in 6.0.1698.0 - Upgrade
Upgrade
NanaZipto a version that resolves this vulnerability.Fixed in 6.5.1742.0
Event History
Frequently Asked Questions
What is the severity of CVE-2026-47223?
The severity of CVE-2026-47223 is rated as medium with a score of 5.4.
How do I fix CVE-2026-47223?
To fix CVE-2026-47223, update NanaZip to version 6.0.1698.0 or later.
What type of vulnerability is CVE-2026-47223?
CVE-2026-47223 is classified as an integer overflow vulnerability leading to a heap out-of-bounds read.
In which versions of NanaZip is CVE-2026-47223 present?
CVE-2026-47223 is present in NanaZip versions from 3.0.1000.0 to before 6.0.1698.0.
What component of NanaZip is affected by CVE-2026-47223?
CVE-2026-47223 affects the Android Verified Boot (AVB) vbmeta image parser in NanaZip.