CVE-2026-64678: Nitrite: Unfiltered Java Deserialization in Legacy v1 Database Migration Path

Is it exploited?

Not on CISA's list. CISA has not added it to the Known Exploited Vulnerabilities catalog as of 10 Nov 2026. If CISA adds it, this page shows it as known exploited.

How likely is exploitation in the next 30 days?

0.7%

EPSS score, percentile 52.2 of all scored records. A probability estimated by FIRST, not a report of exploitation.

CISA's SSVC assessment in the CVE record lists exploitation as poc.

How severe?

9.8 Critical

CVSS v3.1 base score, given by the CNA

What should I do?

CISA has set no required action, because the vulnerability is not in KEV.

No patch or vendor advisory is listed in the CVE record. Check nitrite's advisories.

Which versions are affected?

Affected

• < 4.4.1

Versions by product

Source: CISA KEV 2026.11.10, as of 10 Nov 2026; FIRST EPSS, as of 12 Nov 2026; CVE List, as of 13 Nov 2026. About the data.

Description

Nitrite: Unfiltered Java Deserialization in Legacy v1 Database Migration Path

NOsql Object (NO2 a.k.a Nitrite) database is an open source nosql embedded document store. Prior to version 4.4.1, when Nitrite opens a database file, MVStoreUtils.openOrCreate() automatically checks for a legacy v1-format store and, on detecting one (or hitting a compatibility error while opening), triggers an automatic migration path. This path deserializes stored values using NitriteDataType.deserialize(byte[]), which passes the raw bytes directly to java.io.ObjectInputStream.readObject() via a custom NitriteObjectInputStream subclass. That subclass overrides only readClassDescriptor() — solely to remap a handful of known legacy class names to their current equivalents — and implements no class allowlist, blocklist, or ObjectInputFilter (JEP 290). Any Serializable class reachable on the embedding application's classpath can therefore be instantiated via readObject(), with readObject()/readExternal()/readResolve() callbacks invoked unconditionally. If a suitable gadget class (e.g. from commons-collections or similar) happens to be present on the classpath, this is a precondition for remote code execution. This issue has been patched in version 4.4.1.

Source: CVE List, as of 13 Nov 2026. About the data.

What to do

Advisories and patches

No patch, vendor advisory or mitigation is listed in the CVE record. Check nitrite's own security advisories for a fix, and compare your version with the affected versions below.

This summary is based on the CVE record as of 13 Nov 2026. Check the vendor's advisory before you act: affected versions and fixes can change.

Affected products and versions

Source: CVE List, as of 13 Nov 2026. About the data.

Timeline