python-ldap — security advisory
python-ldap before 3.4.0 is vulnerable to a denial of service when ldap.schema is used for untrusted schema definitions, because of a regular expression denial of service (ReDoS) flaw in the LDAP schema parser. By sending crafted regex input, a remote authenticated attacker could exploit this vulnerability to cause a denial of service condition.
- Products
- python-ldap
- Affected versions
- Not specified
- Fixed versions
- 3.4.0-1
- CVEs
- CVE-2021-46823
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 1 Nov 2026, 01:57 UTC · Revision 1
Source evidence
python-ldap before 3.4.0 is vulnerable to a denial of service when ldap.schema is used for untrusted schema definitions, because of a regular expression denial of service (ReDoS) flaw in the LDAP schema parser. By sending crafted regex input, a remote authenticated attacker could exploit this vulnerability to cause a denial of service condition.
osv:DEBIAN-CVE-2021-46823
python-ldap
Fixed versions: 3.4.0-1
python-ldap
Fixed versions: 3.4.0-1
python-ldap
Fixed versions: 3.4.0-1
Complete source record
{
"id": "81dbd43307a590013b6a66d675d0f6a7fb9c776ab02505c11e3ff31b09ed089a",
"url": "https://osv.dev/vulnerability/DEBIAN-CVE-2021-46823",
"method": "structured",
"payload": {
"kind": "advisory",
"title": "DEBIAN-CVE-2021-46823",
"summary": "python-ldap before 3.4.0 is vulnerable to a denial of service when ldap.schema is used for untrusted schema definitions, because of a regular expression denial of service (ReDoS) flaw in the LDAP schema parser. By sending crafted regex input, a remote authenticated attacker could exploit this vulnerability to cause a denial of service condition.",
"evidence": "osv:DEBIAN-CVE-2021-46823",
"products": [
{
"name": {
"value": "python-ldap",
"evidence": "/affected/0/package/name"
},
"prerequisites": [],
"fixed_versions": [
{
"value": "3.4.0-1",
"evidence": "/affected/0/ranges"
}
],
"affected_versions": []
},
{
"name": {
"value": "python-ldap",
"evidence": "/affected/1/package/name"
},
"prerequisites": [],
"fixed_versions": [
{
"value": "3.4.0-1",
"evidence": "/affected/1/ranges"
}
],
"affected_versions": []
},
{
"name": {
"value": "python-ldap",
"evidence": "/affected/2/package/name"
},
"prerequisites": [],
"fixed_versions": [
{
"value": "3.4.0-1",
"evidence": "/affected/2/ranges"
}
],
"affected_versions": []
}
],
"severity": "medium",
"structured": {
"id": "DEBIAN-CVE-2021-46823",
"aliases": [
"DEBIAN-CVE-2021-46823"
],
"metrics": [
{
"type": "CVSS_V3",
"score": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H"
}
],
"affected": [
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "3.4.0-1"
}
]
}
],
"package": {
"name": "python-ldap",
"purl": "pkg:deb/debian/python-ldap?arch=source&distro=bookworm",
"ecosystem": "Debian:12"
},
"database_specific": {
"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2021-46823.json"
},
"ecosystem_specific": {
"urgency": "not yet assigned"
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "3.4.0-1"
}
]
}
],
"package": {
"name": "python-ldap",
"purl": "pkg:deb/debian/python-ldap?arch=source&distro=trixie",
"ecosystem": "Debian:13"
},
"database_specific": {
"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2021-46823.json"
},
"ecosystem_specific": {
"urgency": "not yet assigned"
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "3.4.0-1"
}
]
}
],
"package": {
"name": "python-ldap",
"purl": "pkg:deb/debian/python-ldap?arch=source&distro=forky",
"ecosystem": "Debian:14"
},
"database_specific": {
"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2021-46823.json"
},
"ecosystem_specific": {
"urgency": "not yet assigned"
}
}
],
"modified": "2026-10-23T18:05:16.947895376Z",
"provider": "osv",
"upstream": [
"CVE-2021-46823"
],
"references": [
"https://security-tracker.debian.org/tracker/CVE-2021-46823"
]
},
"related_cves": [
{
"value": "CVE-2021-46823",
"evidence": "/upstream"
}
],
"security_relevant": true,
"severity_evidence": "/severity/0/score"
},
"source_id": "core-osv",
"document_id": 424306,
"published_at": "2022-06-18T16:15:08.173+00:00"
}