SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityAnalyzed

CVE-2026-42444

From 5.0.1252.0 to before 6.0.1698.0, a denial-of-service vulnerability exists in the littlefs filesystem image parser in NanaZip.

MEDIUM 5.5EPSS 0.11%

Does this matter?

Lower severity and a low EPSS score (0.11%). Track it; it rarely justifies an emergency change on its own.

Description

NanaZip is an open source file archive. From 5.0.1252.0 to before 6.0.1698.0, a denial-of-service vulnerability exists in the littlefs filesystem image parser in NanaZip. The handler's Open method reads BlockCount directly from the attacker-controlled superblock without any validation against the actual file size or any upper-bound ceiling, then iterates BlockCount times, allocating a file-path entry per iteration. A crafted 44-byte littlefs image with BlockCount = 0xFFFFFFFF causes ~4 billion heap allocations, exhausting available memory. This vulnerability is fixed in 6.0.1698.0.

CVSS 3.1
5.5 MEDIUMCVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H
EPSS
0.11% probability · 1th percentile
CISA KEV
Not listed
Weakness
CWE-770
Affected
m2team/nanazip
Source
security-advisories@github.com

Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.