Critical
Security advisory
A flaw was found in gnutls. A use after free issue in client sending key_share extension may lead to memory corruption and other consequences.
- Products
- Not specified
- Affected versions
- Not specified
- Fixed versions
- Not specified
- CVEs
- CVE-2021-20231
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 1 Nov 2026, 05:23 UTC · Revision 1
Source evidence
A flaw was found in gnutls. A use after free issue in client sending key_share extension may lead to memory corruption and other consequences.
osv:CVE-2021-20231
Complete source record
{
"id": "4293833d3a871798eb03202809c510b6bbfc21849d295d9e20253c25bd3de65b",
"url": "https://osv.dev/vulnerability/CVE-2021-20231",
"method": "structured",
"payload": {
"kind": "advisory",
"title": "CVE-2021-20231",
"summary": "A flaw was found in gnutls. A use after free issue in client sending key_share extension may lead to memory corruption and other consequences.",
"evidence": "osv:CVE-2021-20231",
"products": [],
"severity": "critical",
"structured": {
"id": "CVE-2021-20231",
"aliases": [
"CVE-2021-20231"
],
"metrics": [
{
"type": "CVSS_V3",
"score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H"
}
],
"affected": [
{
"ranges": [
{
"repo": "https://github.com/gnutls/gnutls",
"type": "GIT",
"events": [
{
"introduced": "c87f22eec1b412aaafa873ff81b02f52532bfa79"
},
{
"fixed": "3aa1c455cc2fd7f63a0ee6fd90791b46bf06eb79"
}
],
"database_specific": {
"extracted_events": [
{
"cpe": "cpe:2.3:a:gnu:gnutls:*:*:*:*:*:*:*:*",
"range": [
{
"introduced": "3.6.3"
},
{
"fixed": "3.7.1"
}
],
"source": "CPE_RANGE"
}
]
}
}
],
"versions": [
"3.7.0",
"3.6.14",
"3.6.13",
"gnutls_3_6_12",
"3.6.12",
"gnutls_3_6_11_1",
"gnutls_3_6_11",
"gnutls_3_6_10",
"gnutls_3_6_9",
"gnutls_3_6_7",
"gnutls_3_6_6",
"gnutls_3_6_5",
"gnutls_3_6_4",
"gnutls_3_6_3"
],
"database_specific": {
"source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2021-20231.json"
}
},
{
"ranges": [
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"repo": "https://gitlab.com/gnutls/gnutls",
"type": "GIT",
"events": [
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{
"fixed": "3aa1c455cc2fd7f63a0ee6fd90791b46bf06eb79"
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],
"database_specific": {
"extracted_events": [
{
"cpe": "cpe:2.3:a:gnu:gnutls:*:*:*:*:*:*:*:*",
"range": [
{
"introduced": "3.6.3"
},
{
"fixed": "3.7.1"
}
],
"source": "CPE_RANGE"
}
]
}
}
],
"versions": [
"3.7.0",
"3.6.14",
"3.6.13",
"gnutls_3_6_12",
"3.6.12",
"gnutls_3_6_11_1",
"gnutls_3_6_11",
"gnutls_3_6_10",
"gnutls_3_6_9",
"gnutls_3_6_7",
"gnutls_3_6_6",
"gnutls_3_6_5",
"gnutls_3_6_4",
"gnutls_3_6_3"
],
"database_specific": {
"source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2021-20231.json"
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}
],
"modified": "2026-10-24T10:30:28.071378716Z",
"provider": "osv",
"references": [
"https://cert-portal.siemens.com/productcert/html/ssa-398330.html",
"https://lists.apache.org/thread.html/r50661d6f0082709aad9a584431b59ec364f9974b63b07e0800230168%40%3Cissues.spark.apache.org%3E",
"https://lists.apache.org/thread.html/r5d4001031e7790d8c6396c499522b4ed2aab782da87b1a14184793bb%40%3Cissues.spark.apache.org%3E",
"https://lists.apache.org/thread.html/r5f88bed447742fcc5c47bf1c7be965ef450131914a6e1f85feba2779%40%3Cissues.spark.apache.org%3E",
"https://lists.apache.org/thread.html/r6ac143ba6dd98bd4bf6bf010d46e56e254056459721ba18822d611f7%40%3Cissues.spark.apache.org%3E",
"https://lists.apache.org/thread.html/r9cbc69e57276413788e90a6ee16c7c034ea4258d31935b70db2bd158%40%3Cissues.spark.apache.org%3E",
"https://lists.apache.org/thread.html/rcd70a4c88a47a75fd2d5f3ffb7cee8c2a18c713320bd90fdcb57495f%40%3Cissues.spark.apache.org%3E",
"https://lists.apache.org/thread.html/rf5e1256d870193def4a82ad89ab95e63943a313b5ff0d81aa87e4532%40%3Cissues.spark.apache.org%3E",
"https://lists.apache.org/thread.html/rfd5273d72d244178441e6904a2f2b41a3268f569e8092ea0b3b2bb20%40%3Cissues.spark.apache.org%3E",
"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/OSLAE6PP33A7VYRYMYMUVB3U6B26GZER/",
"https://security.netapp.com/advisory/ntap-20210416-0005/",
"https://bugzilla.redhat.com/show_bug.cgi?id=1922276",
"https://www.gnutls.org/security-new.html#GNUTLS-SA-2021-03-10"
],
"provider_metadata": {
"unresolved_ranges": [
{
"cpes": [
"cpe:2.3:o:fedoraproject:fedora:34:*:*:*:*:*:*:*"
],
"vendor_product": "fedoraproject:fedora",
"extracted_events": [
{
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{
"introduced": "34"
},
{
"last_affected": "34"
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],
"source": "CPE_STRING"
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},
{
"cpes": [
"cpe:2.3:o:redhat:enterprise_linux:8.0:*:*:*:*:*:*:*"
],
"vendor_product": "redhat:enterprise_linux",
"extracted_events": [
{
"range": [
{
"introduced": "8.0"
},
{
"last_affected": "8.0"
}
],
"source": "CPE_STRING"
}
]
}
]
}
},
"related_cves": [
{
"value": "CVE-2021-20231",
"evidence": "/id"
}
],
"security_relevant": true,
"severity_evidence": "/severity/0/score"
},
"source_id": "core-osv",
"document_id": 431965,
"published_at": "2021-03-12T19:15:13.037+00:00"
}