glibc — security advisory
In iconvdata/iso-2022-jp-3.c in the GNU C Library (aka glibc) 2.34, remote attackers can force iconv() to emit a spurious '\0' character via crafted ISO-2022-JP-3 data that is accompanied by an internal state reset. This may affect data integrity in certain iconv() use cases. NOTE: the vendor states "the bug cannot be invoked through user input and requires iconv to be invoked with a NULL inbuf, which ought to require a separate application bug to do so unintentionally. Hence there's no security impact to the bug.
- Products
- glibc
- Affected versions
- Not specified
- Fixed versions
- 2.32-5
- CVEs
- CVE-2021-43396
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 30 Oct 2026, 16:46 UTC · Revision 1
Source evidence
In iconvdata/iso-2022-jp-3.c in the GNU C Library (aka glibc) 2.34, remote attackers can force iconv() to emit a spurious '\0' character via crafted ISO-2022-JP-3 data that is accompanied by an internal state reset. This may affect data integrity in certain iconv() use cases. NOTE: the vendor states "the bug cannot be invoked through user input and requires iconv to be invoked with a NULL inbuf, which ought to require a separate application bug to do so unintentionally. Hence there's no security impact to the bug.
osv:DEBIAN-CVE-2021-43396
glibc
Fixed versions: 2.32-5
glibc
Fixed versions: 2.32-5
glibc
Fixed versions: 2.32-5
Complete source record
{
"id": "e9c4585a69110e3776aa507845fd9842c63542168f1474377f25c527d7d9fbbd",
"url": "https://osv.dev/vulnerability/DEBIAN-CVE-2021-43396",
"method": "structured",
"payload": {
"kind": "advisory",
"title": "DEBIAN-CVE-2021-43396",
"summary": "In iconvdata/iso-2022-jp-3.c in the GNU C Library (aka glibc) 2.34, remote attackers can force iconv() to emit a spurious '\\0' character via crafted ISO-2022-JP-3 data that is accompanied by an internal state reset. This may affect data integrity in certain iconv() use cases. NOTE: the vendor states \"the bug cannot be invoked through user input and requires iconv to be invoked with a NULL inbuf, which ought to require a separate application bug to do so unintentionally. Hence there's no security impact to the bug.",
"evidence": "osv:DEBIAN-CVE-2021-43396",
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"evidence": "/affected/0/package/name"
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{
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"severity": "high",
"structured": {
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"aliases": [
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"metrics": [
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],
"modified": "2026-10-15T09:47:39.638761648Z",
"provider": "osv",
"upstream": [
"CVE-2021-43396"
],
"references": [
"https://security-tracker.debian.org/tracker/CVE-2021-43396"
]
},
"related_cves": [
{
"value": "CVE-2021-43396",
"evidence": "/upstream"
}
],
"security_relevant": true,
"severity_evidence": "/severity/0/score"
},
"source_id": "core-osv",
"document_id": 328187,
"published_at": "2021-11-04T20:15:09.223+00:00"
}