CVE-2023-39913 — uimaj
HIGHCVE-2023-39913 is a high-severity (CVSS 8.8) Improper Input Validation vulnerability in org.apache.uima:uimaj. A fix is available for org.apache.uima:uimaj — see the affected versions and patch details below.
Apache UIMA Java SDK Core, Apache UIMA Java SDK CPE, Apache UIMA Java SDK Vinci adapter, Apache UIMA Java SDK tools: Potential untrusted code execution when deserializing certain binary CAS formats
Exploitation Status
No confirmed exploitation observed yet
- A successful exploit gives an attacker total control of the affected component, not partial access.
- CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.
Exploitation and automatability from CISA’s SSVC triage for CVE-2023-39913.
EPSS Exploitation Probability
EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.
How urgent is this, really
CVE-2023-39913 plotted by exploitation likelihood (EPSS) against impact (CVSS). The shaded corner — EPSS 50%+ and CVSS 7.0+ — is where this CVE doesn't sit, though severity or exploitability alone can still warrant action.
Where this sits among everything scored
Of 379,145 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Real counts from FIRST.org, not a sample — log-scaled since the landscape is heavily right-skewed.
Real-World Exposure
org.apache.uima:uimajReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects Maven packages — download data is not available via public APIs for these ecosystems.
Description
Deserialization of Untrusted Data, Improper Input Validation vulnerability in Apache UIMA Java SDK, Apache UIMA Java SDK, Apache UIMA Java SDK, Apache UIMA Java SDK.This issue affects Apache UIMA Java SDK: before 3.5.0.
Users are recommended to upgrade to version 3.5.0, which fixes the issue.
There are several locations in the code where serialized Java objects are deserialized without verifying the data. This affects in particular:
- the deserialization of a Java-serialized CAS, but also other binary CAS formats that include TSI information using the CasIOUtils class;
- the CAS Editor Eclipse plugin which uses the the CasIOUtils class to load data;
- the deserialization of a Java-serialized CAS of the Vinci Analysis Engine service which can receive using Java-serialized CAS objects over network connections;
- the CasAnnotationViewerApplet and the CasTreeViewerApplet;
- the checkpointing feature of the CPE module.
Note that the UIMA framework by default does not start any remotely accessible services (i.e. Vinci) that would be vulnerable to this issue. A user or developer would need to make an active choice to start such a service. However, users or developers may use the CasIOUtils in their own applications and services to parse serialized CAS data. They are affected by this issue unless they ensure that the data passed to CasIOUtils is not a serialized Java object.
When using Vinci or using CasIOUtils in own services/applications, the unrestricted deserialization of Java-serialized CAS files may allow arbitrary (remote) code execution.
As a remedy, it is possible to set up a global or context-specific ObjectInputFilter (cf. https://openjdk.org/jeps/290 and https://openjdk.org/jeps/415 ) if running UIMA on a Java version that supports it.
Note that Java 1.8 does not support the ObjectInputFilter, so there is no remedy when running on this out-of-support platform. An upgrade to a recent Java version is strongly recommended if you need to secure an UIMA version that is affected by this issue.
To mitigate the issue on a Java 9+ platform, you can configure a filter pattern through the "jdk.serialFilter" system property using a semicolon as a separator:
To allow deserializing Java-serialized binary CASes, add the classes:
- org.apache.uima.cas.impl.CASCompleteSerializer
- org.apache.uima.cas.impl.CASMgrSerializer
- org.apache.uima.cas.impl.CASSerializer
- java.lang.String
To allow deserializing CPE Checkpoint data, add the following classes (and any custom classes your application uses to store its checkpoints):
- org.apache.uima.collection.impl.cpm.CheckpointData
- org.apache.uima.util.ProcessTrace
- org.apache.uima.util.impl.ProcessTrace_impl
- org.apache.uima.collection.base_cpm.SynchPoint
Make sure to use "!*" as the final component to the filter pattern to disallow deserialization of any classes not listed in the pattern.
Apache UIMA 3.5.0 uses tightly scoped ObjectInputFilters when reading Java-serialized data depending on the type of data being expected. Configuring a global filter is not necessary with this version.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| ☕Maven | org.apache.uima:uimaj | all versions | 3.5.0org.apache.uima:uimaj:3.5.0 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for org.apache.uima:uimaj, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update org.apache.uima:uimaj to 3.5.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2023-39913 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like CVE-2023-39913 can be triaged on real exposure rather than presence alone.
Tailored to CVE-2023-39913. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is CVE-2023-39913 in your dependencies?
O3 Security finds CVE-2023-39913 across Maven dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.