High
Security advisory
MIT Kerberos 5 (aka krb5) before 1.17.2 and 1.18.x before 1.18.3 allows unbounded recursion via an ASN.1-encoded Kerberos message because the lib/krb5/asn.1/asn1_encode.c support for BER indefinite lengths lacks a recursion limit.
- Products
- Not specified
- Affected versions
- Not specified
- Fixed versions
- Not specified
- CVEs
- CVE-2020-28196
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 1 Nov 2026, 09:33 UTC · Revision 1
Source evidence
MIT Kerberos 5 (aka krb5) before 1.17.2 and 1.18.x before 1.18.3 allows unbounded recursion via an ASN.1-encoded Kerberos message because the lib/krb5/asn.1/asn1_encode.c support for BER indefinite lengths lacks a recursion limit.
osv:CVE-2020-28196
Complete source record
{
"id": "fb88660d862cc7ed41f343994579ed100bf2774eb33c4532fb07735863f9043f",
"url": "https://osv.dev/vulnerability/CVE-2020-28196",
"method": "structured",
"payload": {
"kind": "advisory",
"title": "CVE-2020-28196",
"summary": "MIT Kerberos 5 (aka krb5) before 1.17.2 and 1.18.x before 1.18.3 allows unbounded recursion via an ASN.1-encoded Kerberos message because the lib/krb5/asn.1/asn1_encode.c support for BER indefinite lengths lacks a recursion limit.",
"evidence": "osv:CVE-2020-28196",
"products": [],
"severity": "high",
"structured": {
"id": "CVE-2020-28196",
"aliases": [
"CVE-2020-28196"
],
"metrics": [
{
"type": "CVSS_V3",
"score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H"
}
],
"affected": [
{
"ranges": [
{
"repo": "https://github.com/krb5/krb5",
"type": "GIT",
"events": [
{
"introduced": "0"
},
{
"fixed": "3fae84d40dc6367f94a1d1c8f9846a1f1873abb5"
},
{
"fixed": "4d6a54bca820327a339051853d0716f74985238c"
},
{
"fixed": "57415dda6cf04e73ffc3723be518eddfae599bfd"
}
],
"database_specific": {
"extracted_events": [
{
"cpe": "cpe:2.3:a:mit:kerberos_5:*:*:*:*:*:*:*:*",
"range": [
{
"introduced": "0"
},
{
"fixed": "1.17.2"
}
],
"source": "CPE_RANGE"
},
{
"cpe": "cpe:2.3:a:mit:kerberos_5:*:*:*:*:*:*:*:*",
"range": [
{
"introduced": "1.18.0"
},
{
"fixed": "1.18.3"
}
],
"source": "CPE_RANGE"
},
{
"range": [
{
"fixed": "57415dda6cf04e73ffc3723be518eddfae599bfd"
}
],
"source": "REFERENCES_COMMIT"
}
]
}
}
],
"versions": [
"krb5-1.18.2-final",
"krb5-1.18.1-final",
"krb5-1.18-final",
"krb5-1.18-beta2",
"krb5-1.18-beta1",
"krb5-1.17.1-final",
"kfw-4.2-beta1",
"kfw-4.2-beta1-mit",
"krb5-1.17-final",
"krb5-1.17-beta2",
"krb5-1.17-beta1"
],
"database_specific": {
"source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2020-28196.json",
"vanir_signatures": [
{
"id": "CVE-2020-28196-02fe0993",
"digest": {
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},
"source": "https://github.com/krb5/krb5/commit/57415dda6cf04e73ffc3723be518eddfae599bfd",
"target": {
"file": "src/lib/krb5/asn.1/asn1_encode.c"
},
"deprecated": false,
"signature_type": "Line",
"signature_version": "v1"
},
{
"id": "CVE-2020-28196-16e73268",
"digest": {
"length": 1810,
"function_hash": "57529091313606092540209127447220814768"
},
"source": "https://github.com/krb5/krb5/commit/57415dda6cf04e73ffc3723be518eddfae599bfd",
"target": {
"file": "src/lib/krb5/asn.1/asn1_encode.c",
"function": "get_tag"
},
"deprecated": false,
"signature_type": "Function",
"signature_version": "v1"
},
{
"id": "CVE-2020-28196-4d4662e1",
"digest": {
"length": 411,
"function_hash": "99529815593991416643313083110453829191"
},
"source": "https://github.com/krb5/krb5/commit/57415dda6cf04e73ffc3723be518eddfae599bfd",
"target": {
"file": "src/lib/krb5/asn.1/asn1_encode.c",
"function": "k5_asn1_full_decode"
},
"deprecated": false,
"signature_type": "Function",
"signature_version": "v1"
},
{
"id": "CVE-2020-28196-506ea3b4",
"digest": {
"length": 2735,
"function_hash": "80648222733855492235361015376819548722"
},
"source": "https://github.com/krb5/krb5/commit/57415dda6cf04e73ffc3723be518eddfae599bfd",
"target": {
"file": "src/lib/krb5/asn.1/asn1_encode.c",
"function": "decode_atype"
},
"deprecated": false,
"signature_type": "Function",
"signature_version": "v1"
},
{
"id": "CVE-2020-28196-a9330910",
"digest": {
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"function_hash": "13140286987635898525301114047538986872"
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"source": "https://github.com/krb5/krb5/commit/57415dda6cf04e73ffc3723be518eddfae599bfd",
"target": {
"file": "src/lib/krb5/asn.1/asn1_encode.c",
"function": "decode_sequence"
},
"deprecated": false,
"signature_type": "Function",
"signature_version": "v1"
},
{
"id": "CVE-2020-28196-cfa23556",
"digest": {
"length": 858,
"function_hash": "86798477443948831184784418331358588910"
},
"source": "https://github.com/krb5/krb5/commit/57415dda6cf04e73ffc3723be518eddfae599bfd",
"target": {
"file": "src/lib/krb5/asn.1/asn1_encode.c",
"function": "decode_sequence_of"
},
"deprecated": false,
"signature_type": "Function",
"signature_version": "v1"
},
{
"id": "CVE-2020-28196-faaa6393",
"digest": {
"length": 341,
"function_hash": "41481169286020098270889005944300769622"
},
"source": "https://github.com/krb5/krb5/commit/57415dda6cf04e73ffc3723be518eddfae599bfd",
"target": {
"file": "src/lib/krb5/asn.1/asn1_encode.c",
"function": "split_der"
},
"deprecated": false,
"signature_type": "Function",
"signature_version": "v1"
}
],
"vanir_signatures_modified": "2026-10-24T19:11:42Z"
}
},
{
"ranges": [
{
"repo": "https://github.com/mysql/mysql-server",
"type": "GIT",
"events": [
{
"introduced": "0"
},
{
"last_affected": "7ed30a748964c009d4909cb8b4b22036ebdef239"
}
],
"database_specific": {
"extracted_events": [
{
"cpe": "cpe:2.3:a:oracle:mysql_server:*:*:*:*:*:*:*:*",
"range": [
{
"introduced": "0"
},
{
"last_affected": "8.0.23"
}
],
"source": "CPE_RANGE"
}
]
}
}
],
"versions": [
"mysql-cluster-8.0.23",
"mysql-8.0.23",
"mysql-5.1.4",
"mysql-4.0.4",
"mysql-4.0.2",
"mysql-3.23.36",
"mysql-3.23.33",
"mysql-3.23.32",
"mysql-3.23.31",
"mysql-3.23.30-gamma",
"mysql-3.23.28-gamma",
"mysql-3.23.22-beta"
],
"database_specific": {
"source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2020-28196.json"
}
}
],
"modified": "2026-10-24T19:11:42.425898688Z",
"provider": "osv",
"references": [
"https://cert-portal.siemens.com/productcert/html/ssa-398330.html",
"https://lists.apache.org/thread.html/r58af02e294bd07f487e2c64ffc0a29b837db5600e33b6e698b9d696b%40%3Cissues.bookkeeper.apache.org%3E",
"https://lists.apache.org/thread.html/rf4c02775860db415b4955778a131c2795223f61cb8c6a450893651e4%40%3Cissues.bookkeeper.apache.org%3E",
"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/45KKOZQWIIIW5C45PJVGQ32AXBSYNBE7/",
"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/73IGOG6CZAVMVNS4GGRMOLOZ7B6QVA7F/",
"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/KPH2V3WSQTELROZK3GFCPQDOFLKIZ6H5/",
"https://lists.debian.org/debian-lts-announce/2020/11/msg00011.html",
"https://security.gentoo.org/glsa/202011-17",
"https://security.netapp.com/advisory/ntap-20201202-0001/",
"https://security.netapp.com/advisory/ntap-20210513-0002/",
"https://www.debian.org/security/2020/dsa-4795",
"https://github.com/krb5/krb5/commit/57415dda6cf04e73ffc3723be518eddfae599bfd",
"https://www.oracle.com//security-alerts/cpujul2021.html",
"https://www.oracle.com/security-alerts/cpuApr2021.html",
"https://www.oracle.com/security-alerts/cpuapr2022.html"
],
"provider_metadata": {
"unresolved_ranges": [
{
"cpes": [
"cpe:2.3:a:mit:kerberos_5:*:*:*:*:*:*:*:*"
],
"vendor_product": "mit:kerberos_5",
"extracted_events": [
{
"range": [
{
"fixed": "1.17.2"
},
{
"introduced": "1.18.0"
},
{
"fixed": "1.18.3"
}
],
"source": "CPE_RANGE"
}
]
},
{
"cpes": [
"cpe:2.3:o:fedoraproject:fedora:31:*:*:*:*:*:*:*"
],
"vendor_product": "fedoraproject:fedora",
"extracted_events": [
{
"range": [
{
"introduced": "31"
},
{
"last_affected": "31"
}
],
"source": "CPE_STRING"
}
]
},
{
"cpes": [
"cpe:2.3:a:oracle:communications_cloud_native_core_policy:1.14.0:*:*:*:*:*:*:*"
],
"vendor_product": "oracle:communications_cloud_native_core_policy",
"extracted_events": [
{
"range": [
{
"introduced": "1.14.0"
},
{
"last_affected": "1.14.0"
}
],
"source": "CPE_STRING"
}
]
},
{
"cpes": [
"cpe:2.3:a:oracle:communications_offline_mediation_controller:12.0.0.3.0:*:*:*:*:*:*:*"
],
"vendor_product": "oracle:communications_offline_mediation_controller",
"extracted_events": [
{
"range": [
{
"introduced": "12.0.0.3.0"
},
{
"last_affected": "12.0.0.3.0"
}
],
"source": "CPE_STRING"
}
]
},
{
"cpes": [
"cpe:2.3:a:oracle:communications_pricing_design_center:12.0.0.3.0:*:*:*:*:*:*:*"
],
"vendor_product": "oracle:communications_pricing_design_center",
"extracted_events": [
{
"range": [
{
"introduced": "12.0.0.3.0"
},
{
"last_affected": "12.0.0.3.0"
}
],
"source": "CPE_STRING"
}
]
}
]
}
},
"related_cves": [
{
"value": "CVE-2020-28196",
"evidence": "/id"
}
],
"security_relevant": true,
"severity_evidence": "/severity/0/score"
},
"source_id": "core-osv",
"document_id": 444083,
"published_at": "2020-11-06T08:15:13.86+00:00"
}