CVE-2025-6507
Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.
NVD · uneditedA vulnerability in the h2oai/h2o-3 repository allows attackers to exploit deserialization of untrusted data, potentially leading to arbitrary code execution and reading of system files. This issue affects the latest master branch version 3.47.0.99999. The vulnerability arises from the ability to bypass regular expression filters intended to prevent malicious parameter injection in JDBC connections. Attackers can manipulate spaces between parameters to evade detection, allowing for unauthorized file access and code execution. The vulnerability is addressed in version 3.46.0.8.
Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.
dbcve analysis · high confidenceA deserialization vulnerability in h2o-3's JDBC connection handling allows attackers to bypass regex filters by manipulating whitespace between parameters in JDBC connection strings. This enables arbitrary code execution and unauthorized file system access through maliciously crafted connection parameters.
Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.
CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.
From the vector- Attack vector
- Network
- Complexity
- Low
- Privileges
- None
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- High
- Integrity
- High
- Availability
- High
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.
dbcve checksWork through these to decide whether this CVE applies to you.
-
Identify if h2o-3 is presentLook for h2o-3 JAR files in the environment, check running Java processes for h2o-3, or search for h2o jar files in application directoriesAffected if h2o-3 is installed and running in the environment
-
Determine the h2o-3 versionCheck the h2o-3 JAR file name or version metadata, or query the h2o-3 instance version endpoint if accessibleAffected if The installed version is below 3.46.0.8
-
Verify JDBC connectivity is in useSearch for JDBC connection string configurations, look for h2o JDBC driver usage in code or configuration files, or check for h2o JDBC client imports and usageAffected if JDBC connections are being made to h2o-3
-
Inspect JDBC connection string handlingReview how JDBC connection strings are parsed in your application, specifically looking for code that handles parameter parsing or passes connection strings to h2o-3 JDBC driverAffected if The application parses JDBC connection strings with parameters that could be manipulated with whitespace injection
Environment is affected if h2o-3 version below 3.46.0.8 is installed and JDBC connection handling is in use, as the regex filter bypass in JDBC parameter parsing can be exploited.
Generated from the published advisory. Verify against your own configuration.
Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.
dbcve · scopedUpgrade h2o-3 to version 3.46.0.8 or later to apply the patch that fixes the regex filter bypass in JDBC parameter parsing.
h2o-3 version 3.46.0.8 or later
- Upgrade to h2o-3 version 3.46.0.8 or later which contains the security patch for the JDBC deserialization vulnerability
- If immediate upgrade is not possible, review JDBC connection configurations and ensure no untrusted data is passed to deserialization routines
- Verify that the fix commit (f714edd6b8429c7a7211b779b6ec108a95b7382d) has been applied to your deployment
- After upgrading, test JDBC connectivity to ensure normal functionality is maintained
Generated from the published advisory — verify against the referenced sources before acting.
- Consultation4.0 h
- Implementation2.0 h
- Testing8.0 h
- Review / QA4.0 h
An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $4,928.
Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2025-6507 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.
References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.
Primary sourcesPractitioner notes
ContributedPeer-ranked notes from engineers who’ve handled CVE-2025-6507 in production — separate from our analysis above.
The advisory tells you what broke. It rarely tells you what actually worked. If you’ve dealt with this one, that detail is what the next engineer is searching for.
- The version that genuinely resolved it — not the one the vendor claimed
- A config change or rule that shut the vector down
- A gotcha in the upgrade path that cost you an afternoon
No notes yet
Be the first to add a field note for this CVE — a mitigation you’ve verified, a version caveat, or a link to a working fix. Sign in above to contribute.
A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.
- Verified mitigations, workarounds, and config changes
- Version or environment caveats, and links to real fixes
- No weaponised exploit code, or anything meant to cause harm
- No spam, self-promotion, credentials, or personal data