Nitrite: Unfiltered Java Deserialization in Legacy v1 Database Migration Path
Affects nitrite-mvstore-adapter up to and including 4.4.0 when a file-based database in the legacy v1 format is opened. Fixed in nitrite-java 4.4.1.
Written by anthropic/claude-haiku-5.5 from the sources below. Verify against them.
- Exploited
- No known exploitation
- Fix
- Fixed in 4.4.1
- Who is exposed
- Default setups
Do first: Check every install: default setups are affected.
- Published
- Last modified
- Whether it needs action now or is a reference record, by fixed rules, with why. Last checked is when cve.now last re-read it.What do these mean? →
- Reference
- Last checked
- A 0-100 score for how much a CVE matters across the industry: exploitation, exposure, how widely the software is used, severity and whether a fix exists.What do these mean? →
- 32/100 · provisional
- How many real-world setups can hit the bug, from the vendor's advisory and CISA data. It does not know your setup.What do these mean? →
- Default setups
- Whether working attack code is public (Exploit-DB, Metasploit, Nuclei or GitHub). Public code makes attacks easier.What do these mean? →
- None on Exploit-DB, Metasploit or GitHub
Summary
Nitrite (nitrite-java) has an unsafe deserialization flaw in its legacy v1 database migration path, which runs when a database file is opened. Remotely, without logging in, an attacker can reach this flaw, and if a suitable gadget class is on the application's classpath, it can lead to remote code execution.
Read the original description
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.
Who should check
Teams whose apps open Nitrite .db files from untrusted sources, such as import or restore-backup features, using nitrite-mvstore-adapter 4.4.0 or earlier.
Read the source excerpt
“Applications that open Nitrite database files from untrusted sources”
cve.now Index
- Exploitation?/40Unknown. No CISA SSVC exploitation rating yet
- Exposure22/25Default setups, reachable over the network without a login
- Reach?/20Unknown. No tracked technology or package matched
- Severity9.8/10CVSS 9.8
- No patch0/5No signal
What would change the score
- Would score about 72 if added to CISA KEV
- Would score about 67 if CISA's SSVC rates exploitation active
What to do
Check every install: default setups are affected.
Upgrade to a fixed version: 4.4.1.
Check your systems with an agent
Paste this into a coding or ops agent. It checks your systems read-only and reports a table per asset.
Check whether my systems are affected by CVE-2026-64678 (Nitrite: Unfiltered Java Deserialization in Legacy v1 Database Migration Path), using the cve.now data below. Rules: work read-only. Do not run exploit code, proof-of-concept scripts or scanners that send attack payloads, and do not change any configuration, package, image or deployment. Report findings only. What cve.now has for CVE-2026-64678 (entry last updated 2026-11-11): Affected: - nitrite nitrite-java: fixed in 4.4.1 Fixed versions: 4.4.1. Conditions (all must be true for the bug to be hit): - Opening a file-based Nitrite database whose store is in the legacy v1 format, or that hits a compatibility error while opening, triggers the automatic migration path. (source: https://github.com/nitrite/nitrite-java/security/advisories/GHSA-9297-g93h-86gg) - Affects nitrite-mvstore-adapter up to and including 4.4.0. (source: https://github.com/nitrite/nitrite-java/security/advisories/GHSA-9297-g93h-86gg) Setup: the bug is reachable in a default setup; no special feature or setting is needed. Attacker needs: network access, no login, no user action. CISA KEV: CVE-2026-64678 is not listed as of cve.now's last read. This KEV status is for CVE-2026-64678 only. If you also check another CVE, look up its own KEV status; never assume it from this one. How to check: - Installed software: check what is actually running, not what a repo declares. Read the version from each host, container image and Kubernetes node (the binary's version output, the OS package database, image layers), and check whether the conditions above hold there. Distribution packages may carry a backported fix under an older version number; confirm against the distribution's own advisory. Verify against the linked advisories before concluding, and cite the date you read each one: - https://github.com/nitrite/nitrite-java/security/advisories/GHSA-9297-g93h-86gg - https://github.com/nitrite/nitrite-java/releases/tag/v4.4.1 Do not conclude an asset is unaffected unless you checked it and the evidence covers both its version and the conditions above. If you could not check something, mark it unknown and say what is missing. Report a table with one row per asset and these columns: Asset | Version or build | Status (affected, fixed, not applicable, unknown) | Compensating controls | Exposure (internet-facing, internal, none) | Evidence | Next action. Entry: https://cve.now/CVE-2026-64678 For follow-up questions, use the cve.now MCP server at https://mcp.cve.now/mcp (no authentication), for example get_vulnerability with id CVE-2026-64678.
Timeline
- CVE published
- First seen by cve.now
- Posted on X by cve.now
Affected versions
- nitrite nitrite-java
fixed in 4.4.1
Evidence 4
Vendor advisory · 1
Establishes: Affected and fixed versions.
- Advisory
CVE record · 2
Establishes: The identifier and description.
- Record
- Record
Other links · 1
- Repository
Corrections
None so far.
Something wrong on this page? Report an error. Every fix is listed here.
Questions about CVE-2026-64678
Is CVE-2026-64678 being exploited?
It is not in CISA's Known Exploited Vulnerabilities catalog, and CISA's SSVC assessment does not mark exploitation as active. That does not mean it has not been attacked: vendors and researchers can report attacks before CISA lists them. No public exploit code is tracked.Source: cve.now feed data
What does this mean?
Opening a file-based Nitrite database in the legacy v1 format, or one that causes a compatibility error on open, starts an automatic migration path. That path deserializes the file without filtering, so an attacker-supplied file can make the application instantiate arbitrary Serializable classes and run their callbacks. Remote code execution is possible if a suitable gadget class is on the classpath.Source: github.com
Which versions are affected by CVE-2026-64678?
nitrite-java: before 4.4.1.Source: cve.now feed data
Am I affected, and how do I check?
nitrite-mvstore-adapter versions up to and including 4.4.0 are affected. Check the nitrite-mvstore-adapter version in the project's dependency file or build output. The vulnerable path runs only when a legacy v1 database file is opened or a compatibility error occurs while opening.Source: github.com
How do I fix CVE-2026-64678?
Upgrade nitrite-java to 4.4.1 or later, which the product data lists as the fixed version.Source: github.com