Medium
msgpack-java — security advisory
msgpack-java through 0.9.12 contains an integer overflow vulnerability in MessageUnpacker.skipValue() when processing MAP32 containers with large element counts. Attackers can supply a MAP32 element count at or above 0x40000000 that wraps when doubled, causing the parser cursor to desynchronize and attacker-controlled data to be returned in place of later fields.
- Products
- msgpack-java
- Affected versions
- 0.8.18-2, 0.8.19-1, 0.8.22-2, 0.9.0-1, 0.9.0-2, 0.9.5-1, 0.9.6-1, 0.9.6-1build1
- Fixed versions
- Not specified
- CVEs
- CVE-2026-90473
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 31 Oct 2026, 03:31 UTC · Revision 1
Source evidence
msgpack-java through 0.9.12 contains an integer overflow vulnerability in MessageUnpacker.skipValue() when processing MAP32 containers with large element counts. Attackers can supply a MAP32 element count at or above 0x40000000 that wraps when doubled, causing the parser cursor to desynchronize and attacker-controlled data to be returned in place of later fields.
osv:UBUNTU-CVE-2026-90473
msgpack-java
Fixed versions: Not specified
msgpack-java
Fixed versions: Not specified
msgpack-java
Fixed versions: Not specified
msgpack-java
Fixed versions: Not specified
msgpack-java
Fixed versions: Not specified
Complete source record
{
"id": "7d873a0cf84d8a6344985dfd365cea600fa9289a19f5c49c7550a66ce709dedd",
"url": "https://osv.dev/vulnerability/UBUNTU-CVE-2026-90473",
"method": "structured",
"payload": {
"kind": "advisory",
"title": "UBUNTU-CVE-2026-90473",
"summary": "msgpack-java through 0.9.12 contains an integer overflow vulnerability in MessageUnpacker.skipValue() when processing MAP32 containers with large element counts. Attackers can supply a MAP32 element count at or above 0x40000000 that wraps when doubled, causing the parser cursor to desynchronize and attacker-controlled data to be returned in place of later fields.",
"evidence": "osv:UBUNTU-CVE-2026-90473",
"products": [
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"name": {
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"evidence": "/affected/0/package/name"
},
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"affected_versions": [
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"value": "0.8.18-2",
"evidence": "/affected/0/versions"
},
{
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"evidence": "/affected/0/versions"
}
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{
"name": {
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"evidence": "/affected/1/versions"
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{
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{
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{
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{
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"evidence": "/affected/4/versions"
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{
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],
"severity": "medium",
"structured": {
"id": "UBUNTU-CVE-2026-90473",
"aliases": [
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],
"metrics": [
{
"type": "CVSS_V3",
"score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N"
},
{
"type": "CVSS_V4",
"score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N"
},
{
"type": "Ubuntu",
"score": "medium"
}
],
"affected": [
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
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],
"package": {
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"purl": "pkg:deb/ubuntu/msgpack-java?arch=source&distro=focal",
"ecosystem": "Ubuntu:20.04:LTS"
},
"versions": [
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"database_specific": {
"source": "https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-90473.json"
},
"ecosystem_specific": {
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{
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"package": {
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"purl": "pkg:deb/ubuntu/msgpack-java?arch=source&distro=jammy",
"ecosystem": "Ubuntu:22.04:LTS"
},
"versions": [
"0.8.22-2",
"0.9.0-1",
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"database_specific": {
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"ecosystem": "Ubuntu:24.04:LTS"
},
"versions": [
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"purl": "pkg:deb/ubuntu/msgpack-java?arch=source&distro=stonking",
"ecosystem": "Ubuntu:26.10"
},
"versions": [
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"database_specific": {
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{
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"purl": "pkg:deb/ubuntu/msgpack-java?arch=source&distro=resolute",
"ecosystem": "Ubuntu:26.04:LTS"
},
"versions": [
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"database_specific": {
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"binaries": [
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}
],
"modified": "2026-10-17T13:01:17.019303801Z",
"provider": "osv",
"upstream": [
"CVE-2026-90473"
],
"references": [
"https://ubuntu.com/security/CVE-2026-90473",
"https://www.cve.org/CVERecord?id=CVE-2026-90473",
"https://github.com/msgpack/msgpack-java/issues/1014",
"https://github.com/msgpack/msgpack-java",
"https://github.com/msgpack/msgpack-java/blob/v0.9.12/msgpack-core/src/main/java/org/msgpack/core/MessageUnpacker.java#L573-L581",
"https://www.vulncheck.com/advisories/msgpack-java-through-0.9.12-integer-overflow-via-map32"
]
},
"related_cves": [
{
"value": "CVE-2026-90473",
"evidence": "/upstream"
}
],
"security_relevant": true,
"severity_evidence": "/severity/1/score"
},
"source_id": "core-osv",
"document_id": 361496,
"published_at": "2026-09-12T11:16:00+00:00"
}