CVE-2026-27710: M2Team NanaZip · Integer Underflow
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 4% 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-2026-27710, organizations should upgrade NanaZip to versions 6.0.1638.0 or later, where the vulnerability is fixed. Until upgrades can be applied, restrict access to vulnerable NanaZip versions to trusted users only and avoid opening untrusted or suspicious archive files. Implement application whitelisting and endpoint protection to detect and block attempts to open malicious archives. Monitor system resource usage for unusual spikes that may indicate exploitation attempts. Consider sandboxing or isolating archive extraction processes to limit impact of potential crashes. Educate users about the risks of opening archives from unverified sources to reduce the likelihood of user interaction-based exploitation. Regularly review and update software inventories to identify vulnerable NanaZip installations. Finally, coordinate with software vendors and security teams to stay informed about patches and advisories related to NanaZip.
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, a denial-of-service vulnerability exists in NanaZip’s `.NET Single File Application` parser. A crafted bundle can force an integer underflow in header-size calculation and trigger an unbounded memory allocation attempt during archive open. Versions 6.0.1638.0 and 6.5.1638.0 fix the issue.