NanaZip is the 7-Zip derivative intended for the modern Windows experience. Prior to 6.5.1749.0, NanaZip's seven in-house IInArchive handlers in NanaZip.Codecs unconditionally dereference the caller-supplied Indices array inside Extract when the archive engine signals extract everything by passing Indices as NULL and NumItems as 0xFFFFFFFF. This causes a NULL pointer dereference in the standard Test archive or Extract all code path for WebAssembly, ElectronAsar, Zealfs, Romfs, Ufs, Littlefs, and DotNetSingleFile archives, resulting in a process crash. This issue is fixed in version 6.5.1749.0.
CVE-2026-55783
This low-severity CVE scores 2.4 under a secondary CVSS source (NVD's own analysis pending). EPSS exploit probability: 0.1%, top 98% of all CVEs by exploit prediction. GitHub Security Advisory data not yet ingested — confidence will rise once GHSA publishes (typical lag: hours to days for open-source ecosystem CVEs; never for infrastructure-only CVEs).
- Lower severity and no public exploit yet
No vendor fix yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for a patch.
- CVSS v3
- 2.4
- EG Score
- 2.4(medium)
- EPSS
- 1.6%
- KEV
- Not listed
Published
July 10, 2026
Last Modified
July 10, 2026
References (4)
- security-advisories@githubhttps://github.com/M2Team/NanaZip/commit/5d74d90b737ac7096e5d944a5a3070c5c6a8f894
- security-advisories@githubhttps://github.com/M2Team/NanaZip/releases/tag/6.5.1749.0
- security-advisories@githubhttps://github.com/M2Team/NanaZip/security/advisories/GHSA-q67r-9cfh-xc29
- 134c704f-9b21-4f2e-91b3-4a467353bcc0https://github.com/M2Team/NanaZip/security/advisories/GHSA-q67r-9cfh-xc29
Weakness Classification(1)
MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.
Data Freshness Timeline
(refreshed 9× in last 7d / 9× in last 30d)
Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.
- 2026-07-15 16:57 UTCEPSS rescore
- 2026-07-15 16:57 UTCEPSS rescore
- 2026-07-13 23:26 UTCEG score recompute
- 2026-07-13 22:31 UTCEPSS rescore
- 2026-07-13 06:13 UTCEPSS rescore
- 2026-07-13 06:13 UTCEPSS rescore
- 2026-07-12 05:46 UTCEPSS rescore
- 2026-07-10 17:13 UTCEG score recompute
- 2026-07-10 17:12 UTCMITRE cvelistV5first tracked
Related CVEs(same CWE)
Frequently asked(5)
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Dependency Blast Radius
Explore the affected products and dependency analysis for CVE-2026-55783
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