ruby-oj — security advisory
Oj (Optimized JSON) is a JSON parser and Object marshaller packaged as a Ruby gem. In versions prior to 3.17.2, when in object mode, Oj.dump is vulnerable to a heap buffer overflow when serializing Exception objects with a large :indent value. The serializer allocates a buffer sized for the object's attributes but does not account for the indent bytes added on each write. With indent: 5000, the accumulation of 5,000-byte indent strings overflows the 13,150-byte heap allocation, corrupting adjacent heap memory. This issue has been fixed in version 3.17.2.
- Products
- ruby-oj
- Affected versions
- 3.14.2-1, 3.16.12-1, 3.16.15-1, 3.16.16-1, 3.16.3-1, 3.17.0-1, 3.17.1-1
- Fixed versions
- 3.14.2-1+deb12u1, 3.16.3-1+deb13u1, 3.17.3-1
- CVEs
- CVE-2026-54896
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 1 Nov 2026, 12:16 UTC · Revision 2
Source evidence
Oj (Optimized JSON) is a JSON parser and Object marshaller packaged as a Ruby gem. In versions prior to 3.17.2, when in object mode, Oj.dump is vulnerable to a heap buffer overflow when serializing Exception objects with a large :indent value. The serializer allocates a buffer sized for the object's attributes but does not account for the indent bytes added on each write. With indent: 5000, the accumulation of 5,000-byte indent strings overflows the 13,150-byte heap allocation, corrupting adjacent heap memory. This issue has been fixed in version 3.17.2.
osv:DEBIAN-CVE-2026-54896
ruby-oj
Fixed versions: 3.14.2-1+deb12u1
ruby-oj
Fixed versions: 3.16.3-1+deb13u1
ruby-oj
Fixed versions: 3.17.3-1
Complete source record
{
"id": "9cd6d5a808c89e6ec00ba70866a968add80a3fab7e8de4383c087b049c7240c7",
"url": "https://osv.dev/vulnerability/DEBIAN-CVE-2026-54896",
"method": "structured",
"payload": {
"kind": "advisory",
"title": "DEBIAN-CVE-2026-54896",
"summary": "Oj (Optimized JSON) is a JSON parser and Object marshaller packaged as a Ruby gem. In versions prior to 3.17.2, when in object mode, Oj.dump is vulnerable to a heap buffer overflow when serializing Exception objects with a large :indent value. The serializer allocates a buffer sized for the object's attributes but does not account for the indent bytes added on each write. With indent: 5000, the accumulation of 5,000-byte indent strings overflows the 13,150-byte heap allocation, corrupting adjacent heap memory. This issue has been fixed in version 3.17.2.",
"evidence": "osv:DEBIAN-CVE-2026-54896",
"products": [
{
"name": {
"value": "ruby-oj",
"evidence": "/affected/0/package/name"
},
"prerequisites": [],
"fixed_versions": [
{
"value": "3.14.2-1+deb12u1",
"evidence": "/affected/0/ranges"
}
],
"affected_versions": [
{
"value": "3.14.2-1",
"evidence": "/affected/0/versions"
}
]
},
{
"name": {
"value": "ruby-oj",
"evidence": "/affected/1/package/name"
},
"prerequisites": [],
"fixed_versions": [
{
"value": "3.16.3-1+deb13u1",
"evidence": "/affected/1/ranges"
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],
"affected_versions": [
{
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"evidence": "/affected/1/versions"
}
]
},
{
"name": {
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"evidence": "/affected/2/package/name"
},
"prerequisites": [],
"fixed_versions": [
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],
"affected_versions": [
{
"value": "3.16.12-1",
"evidence": "/affected/2/versions"
},
{
"value": "3.16.15-1",
"evidence": "/affected/2/versions"
},
{
"value": "3.16.16-1",
"evidence": "/affected/2/versions"
},
{
"value": "3.16.3-1",
"evidence": "/affected/2/versions"
},
{
"value": "3.17.0-1",
"evidence": "/affected/2/versions"
},
{
"value": "3.17.1-1",
"evidence": "/affected/2/versions"
}
]
}
],
"severity": "low",
"structured": {
"id": "DEBIAN-CVE-2026-54896",
"aliases": [
"DEBIAN-CVE-2026-54896"
],
"metrics": [
{
"type": "CVSS_V4",
"score": "CVSS:4.0/AV:L/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X"
}
],
"affected": [
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "3.14.2-1+deb12u1"
}
]
}
],
"package": {
"name": "ruby-oj",
"purl": "pkg:deb/debian/ruby-oj?arch=source&distro=bookworm",
"ecosystem": "Debian:12"
},
"versions": [
"3.14.2-1"
],
"database_specific": {
"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-54896.json"
},
"ecosystem_specific": {
"urgency": "not yet assigned"
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "3.16.3-1+deb13u1"
}
]
}
],
"package": {
"name": "ruby-oj",
"purl": "pkg:deb/debian/ruby-oj?arch=source&distro=trixie",
"ecosystem": "Debian:13"
},
"versions": [
"3.16.3-1"
],
"database_specific": {
"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-54896.json"
},
"ecosystem_specific": {
"urgency": "not yet assigned"
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "3.17.3-1"
}
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}
],
"package": {
"name": "ruby-oj",
"purl": "pkg:deb/debian/ruby-oj?arch=source&distro=forky",
"ecosystem": "Debian:14"
},
"versions": [
"3.16.12-1",
"3.16.15-1",
"3.16.16-1",
"3.16.3-1",
"3.17.0-1",
"3.17.1-1"
],
"database_specific": {
"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-54896.json"
},
"ecosystem_specific": {
"urgency": "not yet assigned"
}
}
],
"modified": "2026-10-26T11:47:31.950659026Z",
"provider": "osv",
"upstream": [
"CVE-2026-54896"
],
"references": [
"https://security-tracker.debian.org/tracker/CVE-2026-54896"
]
},
"related_cves": [
{
"value": "CVE-2026-54896",
"evidence": "/upstream"
}
],
"security_relevant": true,
"severity_evidence": "/severity/0/score"
},
"source_id": "core-osv",
"document_id": 450768,
"published_at": "2026-07-01T00:16:32.867+00:00"
}