UBUNTU-CVE-2026-86219 (CVE-2026-86219)
Vulnerability from osv_ubuntu – Published: 2026-09-06 18:17 – Updated: 2026-09-16 11:43 – Source website
VLAI
Details
Authen::SASL::Perl::DIGEST_MD5 versions before 2.2100 for Perl accept replayed authentication responses via unverified nonce in server_step. server_start generates a fresh nonce and sends it in the challenge, and nothing later compares that value against the nonce the client returns. server_step derives the expected digest from the client's own parameters, so a response verifies whenever its digest matches the nonce it carries. The count table it also checks is keyed on the client-supplied nonce and starts empty in each new server object, so a captured first response, carrying nc=00000001, passes that too. RFC 2831 defines the nonce in the response as the value the server sent in the preceding challenge. An attacker who observes one successful qop=auth exchange can replay the captured response against a later session for the same service, host, realm and user, and authenticate as that user without knowing the password.
Severity
9.8 (Critical)
N/A (UNKNOWN)
References
{
"affected": [
{
"ecosystem_specific": {
"binaries": [
{
"binary_name": "libauthen-sasl-perl",
"binary_version": "2.1500-1"
}
]
},
"package": {
"ecosystem": "Ubuntu:14.04:LTS",
"name": "libauthen-sasl-perl",
"purl": "pkg:deb/ubuntu/libauthen-sasl-perl@2.1500-1?arch=source\u0026distro=trusty"
},
"ranges": [
{
"events": [
{
"introduced": "0"
}
],
"type": "ECOSYSTEM"
}
],
"versions": [
"2.1500-1"
]
},
{
"ecosystem_specific": {
"binaries": [
{
"binary_name": "libauthen-sasl-perl",
"binary_version": "2.1600-1"
}
]
},
"package": {
"ecosystem": "Ubuntu:16.04:LTS",
"name": "libauthen-sasl-perl",
"purl": "pkg:deb/ubuntu/libauthen-sasl-perl@2.1600-1?arch=source\u0026distro=xenial"
},
"ranges": [
{
"events": [
{
"introduced": "0"
}
],
"type": "ECOSYSTEM"
}
],
"versions": [
"2.1600-1"
]
},
{
"ecosystem_specific": {
"binaries": [
{
"binary_name": "libauthen-sasl-perl",
"binary_version": "2.1600-1"
}
]
},
"package": {
"ecosystem": "Ubuntu:18.04:LTS",
"name": "libauthen-sasl-perl",
"purl": "pkg:deb/ubuntu/libauthen-sasl-perl@2.1600-1?arch=source\u0026distro=bionic"
},
"ranges": [
{
"events": [
{
"introduced": "0"
}
],
"type": "ECOSYSTEM"
}
],
"versions": [
"2.1600-1"
]
},
{
"ecosystem_specific": {
"binaries": [
{
"binary_name": "libauthen-sasl-perl",
"binary_version": "2.1600-1"
}
]
},
"package": {
"ecosystem": "Ubuntu:20.04:LTS",
"name": "libauthen-sasl-perl",
"purl": "pkg:deb/ubuntu/libauthen-sasl-perl@2.1600-1?arch=source\u0026distro=focal"
},
"ranges": [
{
"events": [
{
"introduced": "0"
}
],
"type": "ECOSYSTEM"
}
],
"versions": [
"2.1600-1"
]
},
{
"ecosystem_specific": {
"binaries": [
{
"binary_name": "libauthen-sasl-perl",
"binary_version": "2.1600-1.1"
}
]
},
"package": {
"ecosystem": "Ubuntu:22.04:LTS",
"name": "libauthen-sasl-perl",
"purl": "pkg:deb/ubuntu/libauthen-sasl-perl@2.1600-1.1?arch=source\u0026distro=jammy"
},
"ranges": [
{
"events": [
{
"introduced": "0"
}
],
"type": "ECOSYSTEM"
}
],
"versions": [
"2.1600-1.1"
]
},
{
"ecosystem_specific": {
"binaries": [
{
"binary_name": "libauthen-sasl-perl",
"binary_version": "2.1700-1"
}
]
},
"package": {
"ecosystem": "Ubuntu:24.04:LTS",
"name": "libauthen-sasl-perl",
"purl": "pkg:deb/ubuntu/libauthen-sasl-perl@2.1700-1?arch=source\u0026distro=noble"
},
"ranges": [
{
"events": [
{
"introduced": "0"
}
],
"type": "ECOSYSTEM"
}
],
"versions": [
"2.1600-3",
"2.1700-1"
]
},
{
"ecosystem_specific": {
"binaries": [
{
"binary_name": "libauthen-sasl-perl",
"binary_version": "2.2000-1"
}
]
},
"package": {
"ecosystem": "Ubuntu:26.04:LTS",
"name": "libauthen-sasl-perl",
"purl": "pkg:deb/ubuntu/libauthen-sasl-perl@2.2000-1?arch=source\u0026distro=resolute"
},
"ranges": [
{
"events": [
{
"introduced": "0"
}
],
"type": "ECOSYSTEM"
}
],
"versions": [
"2.1700-1",
"2.2000-1"
]
}
],
"aliases": [],
"details": "Authen::SASL::Perl::DIGEST_MD5 versions before 2.2100 for Perl accept replayed authentication responses via unverified nonce in server_step. server_start generates a fresh nonce and sends it in the challenge, and nothing later compares that value against the nonce the client returns. server_step derives the expected digest from the client\u0027s own parameters, so a response verifies whenever its digest matches the nonce it carries. The count table it also checks is keyed on the client-supplied nonce and starts empty in each new server object, so a captured first response, carrying `nc=00000001`, passes that too. RFC 2831 defines the nonce in the response as the value the server sent in the preceding challenge. An attacker who observes one successful `qop=auth` exchange can replay the captured response against a later session for the same service, host, realm and user, and authenticate as that user without knowing the password.",
"id": "UBUNTU-CVE-2026-86219",
"modified": "2026-09-16T11:43:11Z",
"published": "2026-09-06T18:17:00Z",
"references": [
{
"type": "REPORT",
"url": "https://ubuntu.com/security/CVE-2026-86219"
},
{
"type": "REPORT",
"url": "https://www.cve.org/CVERecord?id=CVE-2026-86219"
},
{
"type": "REPORT",
"url": "https://lists.security.metacpan.org/cve-announce/msg/43326063/"
}
],
"related": [],
"schema_version": "1.7.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
"type": "CVSS_V3"
},
{
"score": "medium",
"type": "Ubuntu"
}
],
"upstream": [
"CVE-2026-86219"
]
}
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Browse all ATT&CK techniques and the vulnerabilities related to each.
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