CVE-2026-27709 PUBLISHED

NanaZip .NET Single-File Manifest Parser Vulnerable to Out-of-Bounds Read via Unchecked RelativePathLength

Assigner: GitHub_M
Reserved: 23.02.2026 Published: 25.02.2026 Updated: 25.02.2026

NanaZip is an open source file archive. Starting in version 5.0.1252.0 and prior to versions 6.0.1638.0 and 6.5.1638.0, NanaZip’s .NET Single File Application parser has an out-of-bounds read vulnerability in manifest parsing. A crafted bundle can provide a malformed RelativePathLength so the parser constructs a std::string from memory beyond HeaderBuffer, leading to crash and potential in-process memory disclosure. Versions 6.0.1638.0 and 6.5.1638.0 fix the issue.

Metrics

CVSS 4.0

CVSS Vector: CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:P/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
CVSS Score: 5.1

Exploitability Metrics		Vulnerable System Impact Metrics		Subsequent System Impact Metrics
Attack Vector	Local	Confidentiality	None	Confidentiality	None
Attack Complexity	Low	Integrity	None	Integrity	None
Attack Requirements	None	Availability	High	Availability	None
Privileges Required	Low
User Interaction	Passive

CVSS 4.0

Product Status

Vendor	M2Team
Product	NanaZip
Versions	Version >= 5.0.1252.0, < 6.0.1638.0 is affected Version >= 6.1, < 6.5.1638.0 is affected

References

https://github.com/M2Team/NanaZip/security/advisories/GHSA-vr4w-xc78-w6fv

Problem Types

CWE-125: Out-of-bounds Read CWE