HighFix available
json-c, libfastjson — security advisory
json-c through 0.14 has an integer overflow and out-of-bounds write via a large JSON file, as demonstrated by printbuf_memappend.
- Products
- json-c, libfastjson
- Affected versions
- Not specified
- Fixed versions
- 0.13.1+dfsg-8, 1.2304.0-1
- CVEs
- CVE-2020-12762
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 1 Nov 2026, 13:04 UTC · Revision 1
Source evidence
json-c through 0.14 has an integer overflow and out-of-bounds write via a large JSON file, as demonstrated by printbuf_memappend.
osv:DEBIAN-CVE-2020-12762
json-c
Fixed versions: 0.13.1+dfsg-8
json-c
Fixed versions: 0.13.1+dfsg-8
json-c
Fixed versions: 0.13.1+dfsg-8
libfastjson
Fixed versions: 1.2304.0-1
libfastjson
Fixed versions: 1.2304.0-1
libfastjson
Fixed versions: 1.2304.0-1
Complete source record
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"url": "https://osv.dev/vulnerability/DEBIAN-CVE-2020-12762",
"method": "structured",
"payload": {
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"evidence": "osv:DEBIAN-CVE-2020-12762",
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}
],
"modified": "2026-10-26T12:01:34.545925438Z",
"provider": "osv",
"upstream": [
"CVE-2020-12762"
],
"references": [
"https://security-tracker.debian.org/tracker/CVE-2020-12762"
]
},
"related_cves": [
{
"value": "CVE-2020-12762",
"evidence": "/upstream"
}
],
"security_relevant": true,
"severity_evidence": "/severity/0/score"
},
"source_id": "core-osv",
"document_id": 451725,
"published_at": "2020-05-09T18:15:11.283+00:00"
}