CVE-2026-27709Public exploit

Crash and memory disclosure via unchecked path length

Published Feb 25, 2026 · Updated Feb 25, 2026

Out-of-bounds read in NanaZip's .NET Single File Application parser allows attackers to crash the process via a crafted bundle. DotNetSingleFile.cpp decodes an untrusted RelativePathLength and constructs a string without checking that the requested bytes remain within HeaderBuffer. Opening the attacker-supplied file is required; when no crash occurs, adjacent in-process heap bytes appear as garbled path text.

CVSS severity5.1
Medium
EPSS probability0.14%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
Coverage for this vulnerability

See if you're affected

Explore vulnerability checks for your environment with Hinoki.

Book a demo

Summary

What happened

Out-of-bounds read in NanaZip's .NET Single File Application parser allows attackers to crash the process via a crafted bundle. DotNetSingleFile.cpp decodes an untrusted RelativePathLength and constructs a string without checking that the requested bytes remain within HeaderBuffer. Opening the attacker-supplied file is required; when no crash occurs, adjacent in-process heap bytes appear as garbled path text.

The record

CVE
CVE-2026-27709
Published
Feb 25, 2026
Updated
Feb 25, 2026
Vendor
M2-Team
Product
NanaZip
Classifications
CWE-125, T1204.002, T1203
Attack vector
local
Privileges
Unavailable

Timeline

How it unfolded

  1. Feb 25, 2026CVE publishedPublication date reported by the CVE source.
  2. Feb 25, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=>= 5.0.1252.0, < 6.0.1638.0
  2. Affected versionversion=>= 6.1, < 6.5.1638.0

What conditions does exploitation require?

Attack vectorlocal
Required privilegesUnavailable in this record.

What is affected?

M2-Team · NanaZipversion=>= 5.0.1252.0, < 6.0.1638.0; version=>= 6.1, < 6.5.1638.0

Published CVSS scores

6.6NIST NVDCVSS:3.1/AV:L/AC:L/PR:L/UI:R/S:U/C:H/I:N/A:H
5.1GitHub, Inc.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 describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectorlocal
PrivilegesUnavailable
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-125Out-of-bounds Read
T1204.002Malicious File
T1203Exploitation for Client Execution

Public exploit references

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

See the directory against your own environment.

Your stack

Check the software in your environment

Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.

Book a demo