CVE-2026-42446: NanaZip is an open source file archive

Routine

MEDIUM 4.4UPGRADE

CVE-2026-42446 is a medium-severity flaw (CVSS 4.4) affecting nanazip. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.

NanaZip is an open source file archive. From 5.0.1252.0 to before 6.0.1698.0, a stack-based out-of-bounds read exists in the ZealFS filesystem image parser in NanaZip. The vulnerability is triggered when opening a crafted ZealFS v1 filesystem image. An attacker-controlled BitmapSize field in the file header drives an unbounded loop that reads past the end of a stack-allocated ZEALFS_V1_HEADER structure. This vulnerability is fixed in 6.0.1698.0.

Why this priority

No elevated risk signals yet

A fixed release or distro patch exists.

Risk facts

CVSS score	4.4 (Medium)
Attack vector	Local
Attack complexity	Low
Privileges needed	None
User interaction	Required
EPSS exploit chance	0.1% (top 98%)
CISA exploited list	No
Weakness	CWE-125
Published	2026-05-12
Last modified	2026-10-26

Publisher (CNA): GitHub, Inc. · Vendor: m2team

Last updated 2026-10-26 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score

Am I affected?

Timeline

2026-05-12 20:16 UTCPublished CVE record published
2026-10-26 18:10 UTCUpdated Record last modified

m2team nanazip UPGRADE

Affected: >= 5.0.1252.0 and < 6.0.1698.0

Fixed in: 6.0.1698.0

Safe to downgrade to: a release before 5.0.1252.0

1. Check installed version

apt-cache policy nanazip || rpm -q nanazip || nanazip --version

2. UPGRADE to 6.0.1698.0 (Debian / Ubuntu)

sudo apt update && sudo apt install --only-upgrade nanazip

2. UPGRADE (RHEL / Amazon Linux / Fedora)

sudo dnf upgrade nanazip

Note

Distros often backport fixes without changing the version number. Confirm with the distro advisory or changelog.

3. If no update is available yet, DOWNGRADE to a release before 5.0.1252.0 (Debian / Ubuntu)

apt-cache madison nanazip sudo apt install nanazip=<VERSION_BEFORE_5.0.1252.0> sudo apt-mark hold nanazip

3. If no update is available yet, DOWNGRADE (RHEL / Amazon Linux / Fedora)

dnf --showduplicates list nanazip sudo dnf downgrade nanazip-<VERSION_BEFORE_5.0.1252.0> sudo dnf versionlock add nanazip

Downgrade risk

Downgrading can break dependent software and may reopen older bugs. Read the distro advisory first and test on a non-production host.

After downgrade

Restart the service, and keep the package held until a fixed release ships.

Verify at the official source NVD · CVE Program · Report a problem with this page
Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.

Quick answers

How do I fix CVE-2026-42446?

nanazip: upgrade to 6.0.1698.0. Exact commands for each OS are on this page.

Is CVE-2026-42446 being exploited?

CVE-2026-42446 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.

What does CVE-2026-42446 affect?

CVE-2026-42446 affects nanazip. Severity is medium (CVSS 4.4). NanaZip is an open source file archive. From 5.0.1252.0 to before 6.0.1698.0, a stack-based out-of-bounds read exists in the ZealFS filesystem image parser in NanaZip. The vulnerability is triggered when opening a crafted ZealFS v1 filesyst

How urgent is CVE-2026-42446?

Priority 16/100. No elevated risk signals yet.

Related CVEs

CVE-2026-44215 MEDIUM 4.4 UPGRADE NanaZip is an open source file archive
CVE-2026-42355 LOW 3.3 UPGRADE NanaZip is an open source file archive
CVE-2026-42443 LOW 3.3 UPGRADE NanaZip is an open source file archive
CVE-2026-42442 LOW 3.3 UPGRADE NanaZip is an open source file archive
CVE-2026-42444 LOW 3.3 UPGRADE NanaZip is an open source file archive

References

← Back to latest CVEs