CVE-2026-27709: M2Team NanaZip · Out-of-bounds Read
Affects M2Team NanaZipSource CVE Database V5
Not known to be exploited · CVSS 5.1 Medium : upgrade to 6.5.1638.0 or 6.0.1638.0 when convenient.
Data as of 30 Oct 2026, 11:52 UTC
- EPSS
- 0.1% chance of exploitation in 30 days – higher than 6% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in 6.5.1638.0, 6.0.1638.0
CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:P/VC:N/VI:N/VA:H/SC:N/SI:N/SA:NExploitation evidence
Disclosed: evidence found.
CVE published 25 Feb 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 30 Oct 2026.
What to do
Upgrade NanaZip and m2team/NanaZip to 6.5.1638.0 or 6.0.1638.0.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| M2TeamNanaZip | Affected
| Fixed in
|
| M2TeamNanaZip | Affected
| Fixed in
|
GitHubm2team/NanaZippkg:github/m2team/NanaZipOther threats | Affected
| Fixed in
|
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
AI-suggested
To mitigate CVE-2026-27709, organizations should immediately upgrade NanaZip to versions 6.0.1638.0 or 6.5.1638.0, where the vulnerability is patched. Until upgrades can be applied, restrict the use of NanaZip to trusted users and environments, and avoid opening untrusted or suspicious archive files. Implement endpoint security controls that detect and block attempts to open malformed archives. Educate users about the risks of opening archives from unknown or unverified sources to reduce the likelihood of social engineering exploitation. Additionally, consider application whitelisting to prevent execution of unauthorized versions of NanaZip. Monitoring for abnormal application crashes or memory access errors related to NanaZip can help detect exploitation attempts. Finally, maintain regular backups and incident response plans to recover from potential denial-of-service conditions.
Description
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.