CVE-2026-43825: Software Security Vulnerability Vulnerability

HIGH
Advisory Identifier: GHSA-g4fv-7mf3-543r
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CVSS 7.3
CWE-502
Published
Advisory Summary

CVE-2026-43825 is a HIGH (CVSS 7.3) security vulnerability vulnerability (CWE-502: Deserialization of Untrusted Data) affecting Software libraries in the Maven ecosystem. The weakness occurs when the product deserializes untrusted data without sufficiently ensuring that the resulting data will be valid.. Remediation is available in the latest vendor maintenance releases.

CVE-2026-43825 at a Glance

CVE Identifier CVE-2026-43825
GHSA Identifier GHSA-g4fv-7mf3-543r
Severity HIGH
CVSS v3.1 Base Score 7.3
CWE Classification CWE-502: Deserialization of Untrusted Data
Affected Product Software
Package Ecosystem Maven
Published Date
Last Updated

Security Impact

CVSS: 7.3

The security impact metrics below are parsed directly from the CVSS v3.1 vector string (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L).

Attack Vector Network (AV:N)
Attack Complexity Low (AC:L)
Privileges Required None (PR:N)
User Interaction None (UI:N)
Scope Unchanged (S:U)
Confidentiality Low (C:L)
Integrity Low (I:L)
Availability Low (A:L)

How to Fix CVE-2026-43825

To remediate this vulnerability, upgrade all affected Software dependencies to a patched release. Both direct and transitive dependencies should be checked, as frameworks or security libraries may pull in vulnerable versions transitively.

Verify Direct and Transitive Dependencies

Run the following command in your project directory to verify that all resolved dependencies use the patched release: 

mvn dependency:tree

How to Check if You Are Affected

To determine whether your Java application is affected by CVE-2026-43825, inspect your build dependencies using the Maven Dependency Plugin:

mvn dependency:tree

Analyze the terminal output to locate any version of Software in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than the patched release), your application is affected.

Note: The mvn dependency:tree command inspects the resolved dependency graph declared in your project's POM files; it does not perform automated security scanning or inspect runtime dynamic classpaths. Always verify runtime container classpaths and shaded JARs.

Technical Details

Vulnerability Mechanism & Technical Analysis

This vulnerability is classified under CWE-502: Deserialization of Untrusted Data, where the product deserializes untrusted data without sufficiently ensuring that the resulting data will be valid. In Software, software state validation or input boundaries are circumvented during processing. Review the official source advisory statement below for specific affected components, classes, and reproduction details.

Source Advisory Statement

Untrusted Java Deserialization in Apache OpenNLP SvmDoccatModel Versions Affected:   before 3.0.0-M4 (libsvm document categorization module; introduced in   OPENNLP-1808 and only present on the 3.x line) Description: SvmDoccatModel.deserialize(InputStream) reads an attacker-controlled stream with java.io.ObjectInputStream and calls readObject() without an ObjectInputFilter installed. ObjectInputStream materialises every class referenced in the stream before the resulting object is cast to SvmDoccatModel, so the cast that follows readObject() executes only after the foreign object graph has already been deserialised in full. If a Java deserialization gadget chain is available on the consumer's classpath, a crafted payload supplied to deserialize() executes arbitrary code in the JVM that loads it. Apache OpenNLP itself does not ship a known gadget chain, so the realistic risk is to downstream applications that embed the libsvm module alongside vulnerable transitive dependencies. The method is public and static, so any caller can pass an untrusted stream to it directly. The practical impact is remote code execution against processes that load SvmDoccatModel instances from untrusted or semi-trusted origins. Mitigation: 3.x users should upgrade to 3.0.0-M4. Users who cannot upgrade immediately should treat all serialized SvmDoccatModel streams as untrusted input unless their provenance is verified, and should avoid invoking SvmDoccatModel.deserialize() on streams supplied by end users or fetched from third-party sources without integrity checks.

References

NVD — CVE-2026-43825 NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-43825
lists.apache.org/thread/c7kom0pgk9cb... WEB
https://lists.apache.org/thread/c7kom0pgk9cbpfnbooh5m3g85ndf50hn
Software Security Information SECURITY
http://www.openwall.com/lists/oss-security/2026/07/06/9

Frequently Asked Questions

What is CVE-2026-43825?
CVE-2026-43825 is a security vulnerability in Software classified as a security vulnerability vulnerability under CWE-502: Deserialization of Untrusted Data.
Which Software versions are affected?
Affected versions include releases prior to current release patches.
What version fixes CVE-2026-43825?
Upgrading to current release patches (or the latest patched release for your respective branch) resolves the vulnerability.
What is the CVSS score of CVE-2026-43825?
CVE-2026-43825 has a CVSS v3.1 base score of 7.3 (HIGH) with vector string CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L.
What CWE is associated with CVE-2026-43825?
CVE-2026-43825 is classified under CWE-502: Deserialization of Untrusted Data (The product deserializes untrusted data without sufficiently ensuring that the resulting data will be valid.).
How can I check Maven dependencies for CVE-2026-43825?
Run the dependency tree command: 'mvn dependency:tree'. This command lists direct and transitive dependencies in your build configuration so you can verify if a vulnerable version is resolved.
Machine-readable OSV JSON OSV v1.5 Schema
Normalized schema output
View Raw JSON 
{
  "schema_version" : "1.4.0",
  "id" : "GHSA-g4fv-7mf3-543r",
  "modified" : "2026-07-06T21:30:37Z",
  "published" : "2026-07-06T18:31:15Z",
  "aliases" : [ "CVE-2026-43825" ],
  "details" : "Untrusted Java Deserialization in Apache OpenNLP SvmDoccatModel\n\nVersions Affected:\n  before 3.0.0-M4 (libsvm document categorization module; introduced in\n  OPENNLP-1808 and only present on the 3.x line)\n\nDescription:\nSvmDoccatModel.deserialize(InputStream) reads an attacker-controlled\nstream with java.io.ObjectInputStream and calls readObject() without an\nObjectInputFilter installed. ObjectInputStream materialises every class\nreferenced in the stream before the resulting object is cast to\nSvmDoccatModel, so the cast that follows readObject() executes only\nafter the foreign object graph has already been deserialised in full.\n\nIf a Java deserialization gadget chain is available on the consumer's\nclasspath, a crafted payload supplied to\ndeserialize() executes arbitrary code in the JVM that loads it. Apache\nOpenNLP itself does not ship a known gadget chain, so the realistic\nrisk is to downstream applications that embed the libsvm module\nalongside vulnerable transitive dependencies. The method is public and\nstatic, so any caller can pass an untrusted stream to it directly.\n\nThe practical impact is remote code execution against processes that\nload SvmDoccatModel instances from untrusted or semi-trusted origins.\n\nMitigation:\n\n3.x users should upgrade to 3.0.0-M4.\n\nUsers who cannot upgrade immediately should treat all serialized\nSvmDoccatModel streams as untrusted input unless their provenance is\nverified, and should avoid invoking SvmDoccatModel.deserialize() on\nstreams supplied by end users or fetched from third-party sources\nwithout integrity checks.",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L"
  } ],
  "affected" : [ ],
  "references" : [ {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2026-43825"
  }, {
    "type" : "WEB",
    "url" : "https://lists.apache.org/thread/c7kom0pgk9cbpfnbooh5m3g85ndf50hn"
  }, {
    "type" : "WEB",
    "url" : "http://www.openwall.com/lists/oss-security/2026/07/06/9"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-502" ],
    "severity" : "HIGH",
    "github_reviewed" : false,
    "github_reviewed_at" : null,
    "nvd_published_at" : "2026-07-06T17:16:31Z"
  }
}