Security readout for executives and security teams
Plain-English summary
CVE-2026-27710 is a NanaZip denial-of-service issue. A specially crafted .NET single-file application archive can make vulnerable NanaZip versions attempt excessive memory allocation when opened, potentially freezing or crashing the application or host session.
Executive priority
Treat this as a moderate-priority endpoint availability issue. Prioritize updates where NanaZip is used to inspect files from email, downloads, shared drives, or developer workflows.
Technical view
NanaZip’s .NET Single File Application parser has an integer underflow in header-size calculation. In affected versions, opening a crafted bundle can trigger an unbounded allocation attempt. The issue is classified as CWE-191 and affects versions from 5.0.1252.0 before 6.0.1638.0, and 6.1 before 6.5.1638.0.
Likely exposure
Exposure is limited to systems using affected NanaZip versions where a user opens or processes untrusted .NET single-file application bundles. The primary impact is availability, not confidentiality or integrity.
Exploitation context
The CVSS vector indicates local access, low complexity, low privileges, and passive user interaction. The source bundle does not indicate active exploitation, and the CVE is not listed as KEV.
Researcher notes
Evidence supports a parser integer underflow leading to unbounded memory allocation during archive open. No source-provided exploit code, active exploitation report, or broader product impact is included. Validate only with safe version checks and vendor advisory review.
Mitigation direction
- Upgrade NanaZip to version 6.0.1638.0 or 6.5.1638.0 or later, as applicable.
- Avoid opening untrusted .NET single-file application bundles with vulnerable NanaZip versions.
- Check the GitHub security advisory for any updated vendor guidance.
Validation and detection
- Inventory NanaZip installations and record installed versions.
- Flag versions 5.0.1252.0 through below 6.0.1638.0 as affected.
- Flag versions 6.1 through below 6.5.1638.0 as affected.
- Confirm upgraded systems report 6.0.1638.0, 6.5.1638.0, or later.
Public sources used
Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.
Conservative CVE-to-ATT&CK context
These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.
ATT&CK lookup starting points
Use these exact CWE pages and searches to review the Glexia ATT&CK library from this CVE's weakness and description context.
CWE-191: Exact CWE lookup
Use the exact CWE identifier as the starting point before reviewing related ATT&CK behavior. Open the exact CWE lookup page first, then review the ATT&CK searches from that MITRE weakness context. This is a Glexia lookup hint, not an official ATT&CK mapping.
Open ATT&CK lookupCVE-2026-27710 mapping review
Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.
Open ATT&CK lookup- Severity
- Medium
- CVSS
- 5.1 (4.0)
- Known Exploited
- No
- Published
Vector: 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 and ADP enrichment extracted from CVE v5
These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.
CVSS vector scores
1 official scoreWe collect every scored CVSS vector available in the official CNA and ADP containers. When more than one version is present, the table keeps the source vectors side by side instead of collapsing them into the highest score.
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——Primary CVE scoreVulnerability scoring details
Base CVSS 4.0 score
5.1MediumVector: 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
Source materials
- CVE List V5 sourceCVE List V5
- https://github.com/M2Team/NanaZip/security/advisories/GHSA-89qw-8p49-32wfCVE reference · x_refsource_CONFIRM
Products and packages named in the record
CWE details
CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.
Integer Underflow (Wrap or Wraparound)
Integer Underflow (Wrap or Wraparound) represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.