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Fencer Vulns
medium 6.6

CVE-2026-27709 json

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

published 2026-02-25 8 mo ago modified 2026-06-17 4 mo ago also EUVD-2026-8767

cvss
6.6
version 3.1, NVD
cisa kev
Not listed
not in CISA's catalog
epss
0.2%
EPSS 0.2% chance of exploitation in 30 days, percentile 6%
public exploits
0
none known

Summary

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.

Patch / fix

  • m2team nanazip 6.0.1638.0, 6.5.1638.0

CISA SSVC

Exploitation
Proof of concept is public
Automatable
no
Technical impact
partial
Assessed
8 mo ago

Exploit prediction

0.17% chance of exploitation in the next 30 days, higher than 6% of all scored CVEs (FIRST EPSS, 2026-11-08).

Exploits and checks

  • github.com https://github.com/M2Team/NanaZip/security/advisories/GHSA-vr4w-xc78-w6fv referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by version score vector
CNA 4.0 5.1 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
CNA 4.0 5.1 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/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
NVD 3.1 6.6 CVSS:3.1/AV:L/AC:L/PR:L/UI:R/S:U/C:H/I:N/A:H

Affected products

  • M2Team NanaZip

Classification

Weakness

References

Sources

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

CPEs and fixed versions use Anchore's correction of NVD's data: Added CPE configurations because not yet analyzed by NVD.