CVE-2026-55780: CWE-248: Uncaught Exception in M2Team NanaZip
NanaZip versions prior to 6.5.1749.0 contain a vulnerability in the .NET single-file bundle handler where the extraction buffer size is derived from an unvalidated Size field. This can lead to uncaught exceptions such as std::bad_alloc or std::length_error escaping across COM boundaries and crashing the process. The issue is fixed in version 6.5.1749.0. The vulnerability has a low severity score and does not have known exploits in the wild.
AI Analysis
Technical Summary
CVE-2026-55780 affects NanaZip, a 7-Zip derivative for Windows. The vulnerability arises because the .NET single-file bundle handler in NanaZip.Codecs.Archive.DotNetSingleFile.cpp sizes its extraction buffer based on the bundle entry Size field, which is only checked for sign but not validated against the actual file size. A crafted bundle can cause an attacker-controlled allocation inside the Extract function, resulting in exceptions (std::bad_alloc or std::length_error) escaping across the COM STDMETHODCALLTYPE boundary and causing a process crash. This denial-of-service condition is resolved in NanaZip version 6.5.1749.0.
Potential Impact
An attacker can craft a malicious bundle that triggers uncaught exceptions during extraction, causing the NanaZip process to crash. This results in a denial-of-service condition. There is no indication of code execution or data corruption. The vulnerability requires local access with low privileges and user interaction to trigger.
Mitigation Recommendations
Upgrade NanaZip to version 6.5.1749.0 or later where this issue is fixed. No other mitigations are indicated. Patch status is confirmed fixed in 6.5.1749.0.
CVE-2026-55780: CWE-248: Uncaught Exception in M2Team NanaZip
Description
NanaZip versions prior to 6.5.1749.0 contain a vulnerability in the .NET single-file bundle handler where the extraction buffer size is derived from an unvalidated Size field. This can lead to uncaught exceptions such as std::bad_alloc or std::length_error escaping across COM boundaries and crashing the process. The issue is fixed in version 6.5.1749.0. The vulnerability has a low severity score and does not have known exploits in the wild.
CVSS v4.0
Score 2.4low
Affected software
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AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-55780 affects NanaZip, a 7-Zip derivative for Windows. The vulnerability arises because the .NET single-file bundle handler in NanaZip.Codecs.Archive.DotNetSingleFile.cpp sizes its extraction buffer based on the bundle entry Size field, which is only checked for sign but not validated against the actual file size. A crafted bundle can cause an attacker-controlled allocation inside the Extract function, resulting in exceptions (std::bad_alloc or std::length_error) escaping across the COM STDMETHODCALLTYPE boundary and causing a process crash. This denial-of-service condition is resolved in NanaZip version 6.5.1749.0.
Potential Impact
An attacker can craft a malicious bundle that triggers uncaught exceptions during extraction, causing the NanaZip process to crash. This results in a denial-of-service condition. There is no indication of code execution or data corruption. The vulnerability requires local access with low privileges and user interaction to trigger.
Mitigation Recommendations
Upgrade NanaZip to version 6.5.1749.0 or later where this issue is fixed. No other mitigations are indicated. Patch status is confirmed fixed in 6.5.1749.0.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- GitHub_M
- Date Reserved
- 2026-06-17T14:40:28.379Z
- Cvss Version
- 4.0
- State
- PUBLISHED
- Remediation Level
- null
Threat ID: 6a51295b68715ace43e3b81c
Added to database: 07/10/2026, 17:18:19 UTC
Last enriched: 07/10/2026, 17:33:08 UTC
Last updated: 07/10/2026, 17:33:08 UTC
Views: 3
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