CVE-2025-11919
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 · uneditedThe default JVM can access files and directories under `/tmp/` including the `$TemporaryDirectory` of other users on the same cloud instance (`/tmp/UserTemporaryFiles/`). The `-init` file for the the JVM initialization exists in the vulnerable directory during the startup of the JVM. An attacker with access to the shared `/tmp/` space can preemptively create or replace `.jar` files or directories (via the `-init` file) that the victim JVM will resolve first in its classpath. By strategically placing a malicious version of a commonly used library (e.g., `commons-io`) in a location that is included in the classpath before the legitimate version, an attacker can cause the JVM to load the malicious class during startup, thereby executing the attacker's code.
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 confidenceThe JVM uses `/tmp/` (a shared directory on cloud instances) for initialization files during startup. Attackers with access to `/tmp/` can place malicious `.jar` files (e.g., spoofing `commons-io`) that get loaded before legitimate libraries due to classpath ordering, achieving arbitrary code execution during JVM startup.
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
- Low
- User interaction
- None
- Scope
- Changed
- Confidentiality
- High
- Integrity
- High
- Availability
- None
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:N
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.
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Check the JVM temporary directory configurationRun `java -XshowSettings:properties -version 2>&1 | grep java.io.tmpdir` to see what temp directory the JVM is configured to useAffected if The value is set to `/tmp/` or is not a private, user-specific directory
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Verify /tmp/ permissions allow other users to writeRun `ls -ld /tmp/` and check if the directory has world-write permissions (drwxrwxrwt) or group-write permissions that include other usersAffected if The directory is world-writable or group-writable by users who should not have access to place files in the JVM's temp directory
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Inspect JVM classpath for /tmp/ entriesRun `echo $CLASSPATH` and check for any paths containing `/tmp/`, or examine your application startup scripts for `-cp` or `-classpath` arguments that include `/tmp/`Affected if The classpath includes any directory under `/tmp/` or allows loading of JAR files from temporary locations
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Check for unsafe file handling in JVM optionsReview JVM startup scripts for `-Djava.io.tmpdir` settings: `grep -r "java.io.tmpdir" /etc/java/ /opt/*/conf/ 2>/dev/null` or check application startup scriptsAffected if No `-Djava.io.tmpdir` override is set, meaning the default `/tmp/` is being used
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Assess multi-user environment riskIdentify if the system is a cloud instance or shared environment where untrusted users may have local access: `who` or `users` command, and check for multiple UIDs in `/etc/passwd` with shell accessAffected if The system is a cloud/multi-user instance where untrusted local users can write to shared /tmp/
A user is affected if the JVM uses the default /tmp/ directory and that directory is writable by other users on the system, allowing them to place malicious JAR files that get loaded during JVM startup.
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.
From vendor dataConfigure the JVM to use a private temporary directory via `-Djava.io.tmpdir` or implement proper file permissions on `/tmp/` to prevent unauthorized file placement by other users.
- Consultation6.0 h
- Implementation12.0 h
- Testing6.0 h
- Review / QA3.0 h
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Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2025-11919 — 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-2025-11919 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
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- Version or environment caveats, and links to real fixes
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