DEBIAN-CVE-2026-42440
OOM Denial of Service via Unbounded Array Allocation in Apache OpenNLP AbstractModelReader Versions Affected: before 1.9.5 before 2.5.9 before 3.0.0-M3 Description: The AbstractModelReader methods getOutcomes(), getOutcomePatterns(), and getPredicates() each read a 32-bit signed integer count field from a binary model stream and pass that value directly to an array allocation (new String[numOutcomes], new int[numOCTypes][], new String[NUM_PREDS]) without validating that the value is non-negative or within a reasonable bound. The count is therefore fully attacker-controlled when the model file originates from an untrusted source. A crafted .bin model file in which any of these count fields is set to Integer.MAX_VALUE (or any value large enough to exhaust the available heap) triggers an OutOfMemoryError at the array allocation itself, before the corresponding label or pattern data is consumed from the stream. The error occurs very early in deserialization: for a GIS model, getOutcomes() is reached after only the model-type string, the correction constant, and the correction parameter have been read; so the attacker pays no meaningful size cost to weaponize a payload, and a single small file can crash a JVM that loads it. Any code path that deserializes a .bin model is affected, including direct use of GenericModelReader and any higher-level component that delegates to it during model load. The practical impact is denial of service against processes that load model files from un
DEBIAN-CVE-2026-42440
Primary source · Revision 1
Imported from structured advisory data. Source references identify upstream records or fields; verify affected versions and your deployed configuration.
Security context
Source reference: osv:DEBIAN-CVE-2026-42440
apache-opennlp
Source reference: /affected/0/package/name
- Affected versions
- 2.1.0-1
Source reference:
/affected/0/versions2.2.0-1Source reference:
/affected/0/versions2.2.0-1~expSource reference:
/affected/0/versions2.3.0-1Source reference:
/affected/0/versions2.3.1-1Source reference:
/affected/0/versions2.3.1-2Source reference:
/affected/0/versions2.3.2-1Source reference:
/affected/0/versions2.3.3-1Source reference:
/affected/0/versions2.4.0-1Source reference:
/affected/0/versions2.5.0-1Source reference:
/affected/0/versions2.5.1-1Source reference:
/affected/0/versions2.5.12-1Source reference:
/affected/0/versions2.5.2-1Source reference:
/affected/0/versions2.5.3-1Source reference:
/affected/0/versions2.5.9-1Source reference:
/affected/0/versions - Fixed versions
- Not stated in this record
- Prerequisites
- Not stated in this record
apache-opennlp
Source reference: /affected/1/package/name
- Affected versions
- 2.5.12-1
Source reference:
/affected/1/versions2.5.3-1Source reference:
/affected/1/versions2.5.9-1Source reference:
/affected/1/versions - Fixed versions
- Not stated in this record
- Prerequisites
- Not stated in this record
apache-opennlp
Source reference: /affected/2/package/name
- Affected versions
- 2.5.3-1
Source reference:
/affected/2/versions - Fixed versions
- 2.5.9-1
Source reference:
/affected/2/ranges - Prerequisites
- Not stated in this record
Structured affected-version data
Original package identities and version rules from this source.
[
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
}
]
}
],
"package": {
"name": "apache-opennlp",
"purl": "pkg:deb/debian/apache-opennlp?arch=source&distro=bookworm",
"ecosystem": "Debian:12"
},
"versions": [
"2.1.0-1",
"2.2.0-1",
"2.2.0-1~exp",
"2.3.0-1",
"2.3.1-1",
"2.3.1-2",
"2.3.2-1",
"2.3.3-1",
"2.4.0-1",
"2.5.0-1",
"2.5.1-1",
"2.5.12-1",
"2.5.2-1",
"2.5.3-1",
"2.5.9-1"
],
"database_specific": {
"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-42440.json"
},
"ecosystem_specific": {
"urgency": "not yet assigned"
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
}
]
}
],
"package": {
"name": "apache-opennlp",
"purl": "pkg:deb/debian/apache-opennlp?arch=source&distro=trixie",
"ecosystem": "Debian:13"
},
"versions": [
"2.5.12-1",
"2.5.3-1",
"2.5.9-1"
],
"database_specific": {
"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-42440.json"
},
"ecosystem_specific": {
"urgency": "not yet assigned"
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "2.5.9-1"
}
]
}
],
"package": {
"name": "apache-opennlp",
"purl": "pkg:deb/debian/apache-opennlp?arch=source&distro=forky",
"ecosystem": "Debian:14"
},
"versions": [
"2.5.3-1"
],
"database_specific": {
"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-42440.json"
},
"ecosystem_specific": {
"urgency": "not yet assigned"
}
}
]Publisher severity
No explicit severity was provided.
- Event
- #56494 · Revision 1
- Added to Heist Feed
- Publisher date