High
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
- Not specified
- Affected versions
- Not specified
- Fixed versions
- Not specified
- CVEs
- CVE-2021-43396
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 1 Nov 2026, 07:57 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:CVE-2021-43396
Complete source record
{
"id": "9397002bda91adcaa24f98d07eb550d286ea2635ec5e5d1d495865818155730d",
"url": "https://osv.dev/vulnerability/CVE-2021-43396",
"method": "structured",
"payload": {
"kind": "advisory",
"title": "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:CVE-2021-43396",
"products": [],
"severity": "high",
"structured": {
"id": "CVE-2021-43396",
"aliases": [
"CVE-2021-43396"
],
"metrics": [
{
"type": "CVSS_V3",
"score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N"
}
],
"affected": [
{
"ranges": [
{
"repo": "https://github.com/bminor/glibc",
"type": "GIT",
"events": [
{
"introduced": "ae37d06c7d127817ba43850f0f898b793d42aea7"
},
{
"last_affected": "ae37d06c7d127817ba43850f0f898b793d42aea7"
}
],
"database_specific": {
"extracted_events": [
{
"cpe": "cpe:2.3:a:gnu:glibc:2.34:*:*:*:*:*:*:*",
"range": [
{
"introduced": "2.34"
},
{
"last_affected": "2.34"
}
],
"source": "CPE_STRING"
}
]
}
}
],
"versions": [
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"glibc-2.34"
],
"database_specific": {
"source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2021-43396.json"
}
},
{
"ranges": [
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"repo": "https://sourceware.org/git/glibc.git",
"type": "GIT",
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{
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],
"database_specific": {
"extracted_events": [
{
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"range": [
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},
{
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}
],
"source": "CPE_STRING"
}
]
}
}
],
"versions": [
"2.34",
"glibc-2.34"
],
"database_specific": {
"source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2021-43396.json"
}
}
],
"modified": "2026-10-24T10:31:00.825304227Z",
"provider": "osv",
"references": [
"https://cert-portal.siemens.com/productcert/html/ssa-398330.html",
"https://sourceware.org/git/?p=glibc.git%3Ba=commit%3Bh=ff012870b2c02a62598c04daa1e54632e020fd7d",
"https://sourceware.org/bugzilla/show_bug.cgi?id=28524",
"https://www.oracle.com/security-alerts/cpujul2022.html",
"https://blog.tuxcare.com/vulnerability/vulnerability-in-iconv-identified-by-tuxcare-team-cve-2021-43396"
],
"provider_metadata": {
"unresolved_ranges": [
{
"cpes": [
"cpe:2.3:a:oracle:communications_cloud_native_core_binding_support_function:22.1.3:*:*:*:*:*:*:*"
],
"vendor_product": "oracle:communications_cloud_native_core_binding_support_function",
"extracted_events": [
{
"range": [
{
"introduced": "22.1.3"
},
{
"last_affected": "22.1.3"
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],
"source": "CPE_STRING"
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},
{
"cpes": [
"cpe:2.3:a:oracle:communications_cloud_native_core_network_function_cloud_native_environment:22.1.0:*:*:*:*:*:*:*"
],
"vendor_product": "oracle:communications_cloud_native_core_network_function_cloud_native_environment",
"extracted_events": [
{
"range": [
{
"introduced": "22.1.0"
},
{
"last_affected": "22.1.0"
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],
"source": "CPE_STRING"
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{
"cpes": [
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"cpe:2.3:a:oracle:communications_cloud_native_core_network_repository_function:22.2.0:*:*:*:*:*:*:*"
],
"vendor_product": "oracle:communications_cloud_native_core_network_repository_function",
"extracted_events": [
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"range": [
{
"introduced": "22.1.2"
},
{
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},
{
"introduced": "22.2.0"
},
{
"last_affected": "22.2.0"
}
],
"source": "CPE_STRING"
}
]
},
{
"cpes": [
"cpe:2.3:a:oracle:communications_cloud_native_core_security_edge_protection_proxy:22.1.1:*:*:*:*:*:*:*"
],
"vendor_product": "oracle:communications_cloud_native_core_security_edge_protection_proxy",
"extracted_events": [
{
"range": [
{
"introduced": "22.1.1"
},
{
"last_affected": "22.1.1"
}
],
"source": "CPE_STRING"
}
]
},
{
"cpes": [
"cpe:2.3:a:oracle:communications_cloud_native_core_unified_data_repository:22.2.0:*:*:*:*:*:*:*"
],
"vendor_product": "oracle:communications_cloud_native_core_unified_data_repository",
"extracted_events": [
{
"range": [
{
"introduced": "22.2.0"
},
{
"last_affected": "22.2.0"
}
],
"source": "CPE_STRING"
}
]
},
{
"cpes": [
"cpe:2.3:a:oracle:enterprise_operations_monitor:4.3:*:*:*:*:*:*:*",
"cpe:2.3:a:oracle:enterprise_operations_monitor:4.4:*:*:*:*:*:*:*",
"cpe:2.3:a:oracle:enterprise_operations_monitor:5.0:*:*:*:*:*:*:*"
],
"vendor_product": "oracle:enterprise_operations_monitor",
"extracted_events": [
{
"range": [
{
"introduced": "4.3"
},
{
"last_affected": "4.3"
},
{
"introduced": "4.4"
},
{
"last_affected": "4.4"
},
{
"introduced": "5.0"
},
{
"last_affected": "5.0"
}
],
"source": "CPE_STRING"
}
]
}
]
}
},
"related_cves": [
{
"value": "CVE-2021-43396",
"evidence": "/id"
}
],
"security_relevant": true,
"severity_evidence": "/severity/0/score"
},
"source_id": "core-osv",
"document_id": 439635,
"published_at": "2021-11-04T20:15:09.223+00:00"
}