
CVE catalog
CVE-2026-43825
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 l
- Severity
- High · CVSS 7.3
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L - Published
- Source
- [NVD] · [CVE record]
- EPSS
- 13.92% · Oct 25, 2026
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.
Vulnerable and fixed packages
Distribution-reported package versions and fixes. These do not depend on matching against the OpenFactory package catalog.
| Distribution | Package | Release | Version | Status |
|---|---|---|---|---|
| Debian | apache-opennlp | sid | 2.5.12-1 | not affected |
| Debian | apache-opennlp | forky | 2.5.12-1 | not affected |
| Debian | apache-opennlp | trixie | 2.5.3-1 | not affected |
| Debian | apache-opennlp | bookworm | 2.1.0-1 | not affected |
| Cpe | opennlp | Not reported | Not reported | unknown |
| Cpe | opennlp | Not reported | Not reported | unknown |
Fixed-version evidence
| Distribution | Package | Type | Release | Fixed version | Urgency | Origin | Bugs |
|---|---|---|---|---|---|---|---|
| Debian | apache-opennlp | source | sid | Not affected | unimportant | Not reported | Not reported |
| Debian | apache-opennlp | source | forky | Not affected | unimportant | Not reported | Not reported |
| Debian | apache-opennlp | source | trixie | Not affected | unimportant | Not reported | Not reported |
| Debian | apache-opennlp | source | bookworm | Not affected | unimportant | Not reported | Not reported |
OpenFactory catalog packages
[Debian 12 (Bookworm)]
- [libapache-opennlp-java]Not affected
Source package: [apache-opennlp]
Details (2)
2.1.0-1· all · bookwormNot affected
nvd · apache-opennlp · debian · bookworm
2.1.0-1· all · bookwormNot affected
nvd · apache-opennlp · debian · bookworm
- [opennlp]Not affected
Source package: [apache-opennlp]
Details (2)
2.1.0-1· all · bookwormNot affected
nvd · apache-opennlp · debian · bookworm
2.1.0-1· all · bookwormNot affected
nvd · apache-opennlp · debian · bookworm
Observed:
References
- [http://www.openwall.com/lists/oss-security/2026/07/06/9]
- [https://lists.apache.org/thread/c7kom0pgk9cbpfnbooh5m3g85ndf50hn]
- [https://nvd.nist.gov/vuln/detail/CVE-2026-43825]
- [https://security-tracker.debian.org/tracker/CVE-2026-43825]
- [https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-43825.json]
[Debian Security Tracker] · [FIRST EPSS] · [National Vulnerability Database (NVD)] · [Red Hat security advisories and VEX]