CVE-2026-27710Public exploit

Process crash via unchecked bundle header offset

Published Feb 25, 2026 · Updated Feb 25, 2026

Integer underflow in affected M2-Team NanaZip releases allows local users to crash the process by opening a crafted .NET bundle. NanaZip.Codecs.Archive.DotNetSingleFile.cpp subtracts an unchecked, signed BundleHeaderOffset from BundleSize and converts the result to size_t for a vector allocation. Exploitation requires a user to open an attacker-supplied file and causes memory exhaustion or a NanaZip process crash, with no reported data disclosure or modification.

CVSS severity5.1
Medium
EPSS probability0.13%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Integer underflow in affected M2-Team NanaZip releases allows local users to crash the process by opening a crafted .NET bundle. NanaZip.Codecs.Archive.DotNetSingleFile.cpp subtracts an unchecked, signed BundleHeaderOffset from BundleSize and converts the result to size_t for a vector allocation. Exploitation requires a user to open an attacker-supplied file and causes memory exhaustion or a NanaZip process crash, with no reported data disclosure or modification.

The record

CVE
CVE-2026-27710
Published
Feb 25, 2026
Updated
Feb 25, 2026
Vendor
M2-Team
Product
NanaZip
Classifications
CWE-191, T1499.004
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

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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

5.0NIST NVDCVSS:3.1/AV:L/AC:L/PR:L/UI:R/S:U/C:N/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 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectorlocal
PrivilegesUnavailable
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-191Integer Underflow (Wrap or Wraparound)
T1499.004Application or System Exploitation

Public exploit references

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

Technologies

Your stack

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Your stack

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