HighFix available
soupsieve — security advisory
Soup Sieve is a CSS selector library designed to be used with Beautiful Soup 4. Prior to 2.8.4, the CSS selector parser in soupsieve allocates unbounded memory when compiling large comma-separated selector lists, allowing an attacker who can supply a crafted selector string to soupsieve.compile() or Beautiful Soup .select() / .select_one() to allocate hundreds of megabytes of heap memory from a relatively small input and cause denial of service. This issue is fixed in version 2.8.4.
- Products
- soupsieve
- Affected versions
- 2.3.2-1, 2.4-1, 2.4.1-1, 2.4.1-2, 2.5-1, 2.6-1, 2.7-1, 2.7-2, 2.8.1-1, 2.8.3-1, 2.8.4-1
- Fixed versions
- 2.8.4-1
- CVEs
- CVE-2026-49476
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 1 Nov 2026, 09:53 UTC · Revision 2
Source evidence
Soup Sieve is a CSS selector library designed to be used with Beautiful Soup 4. Prior to 2.8.4, the CSS selector parser in soupsieve allocates unbounded memory when compiling large comma-separated selector lists, allowing an attacker who can supply a crafted selector string to soupsieve.compile() or Beautiful Soup .select() / .select_one() to allocate hundreds of megabytes of heap memory from a relatively small input and cause denial of service. This issue is fixed in version 2.8.4.
osv:DEBIAN-CVE-2026-49476
soupsieve
Fixed versions: Not specified
soupsieve
Fixed versions: Not specified
soupsieve
Fixed versions: 2.8.4-1
Complete source record
{
"id": "8f71122aa92f03863de490f20b760ca282a3ffa3cf6e92773c12f26b2261bad7",
"url": "https://osv.dev/vulnerability/DEBIAN-CVE-2026-49476",
"method": "structured",
"payload": {
"kind": "advisory",
"title": "DEBIAN-CVE-2026-49476",
"summary": "Soup Sieve is a CSS selector library designed to be used with Beautiful Soup 4. Prior to 2.8.4, the CSS selector parser in soupsieve allocates unbounded memory when compiling large comma-separated selector lists, allowing an attacker who can supply a crafted selector string to soupsieve.compile() or Beautiful Soup .select() / .select_one() to allocate hundreds of megabytes of heap memory from a relatively small input and cause denial of service. This issue is fixed in version 2.8.4.",
"evidence": "osv:DEBIAN-CVE-2026-49476",
"products": [
{
"name": {
"value": "soupsieve",
"evidence": "/affected/0/package/name"
},
"prerequisites": [],
"fixed_versions": [],
"affected_versions": [
{
"value": "2.3.2-1",
"evidence": "/affected/0/versions"
},
{
"value": "2.4-1",
"evidence": "/affected/0/versions"
},
{
"value": "2.4.1-1",
"evidence": "/affected/0/versions"
},
{
"value": "2.4.1-2",
"evidence": "/affected/0/versions"
},
{
"value": "2.5-1",
"evidence": "/affected/0/versions"
},
{
"value": "2.6-1",
"evidence": "/affected/0/versions"
},
{
"value": "2.7-1",
"evidence": "/affected/0/versions"
},
{
"value": "2.7-2",
"evidence": "/affected/0/versions"
},
{
"value": "2.8.1-1",
"evidence": "/affected/0/versions"
},
{
"value": "2.8.3-1",
"evidence": "/affected/0/versions"
},
{
"value": "2.8.4-1",
"evidence": "/affected/0/versions"
}
]
},
{
"name": {
"value": "soupsieve",
"evidence": "/affected/1/package/name"
},
"prerequisites": [],
"fixed_versions": [],
"affected_versions": [
{
"value": "2.7-1",
"evidence": "/affected/1/versions"
},
{
"value": "2.7-2",
"evidence": "/affected/1/versions"
},
{
"value": "2.8.1-1",
"evidence": "/affected/1/versions"
},
{
"value": "2.8.3-1",
"evidence": "/affected/1/versions"
},
{
"value": "2.8.4-1",
"evidence": "/affected/1/versions"
}
]
},
{
"name": {
"value": "soupsieve",
"evidence": "/affected/2/package/name"
},
"prerequisites": [],
"fixed_versions": [
{
"value": "2.8.4-1",
"evidence": "/affected/2/ranges"
}
],
"affected_versions": [
{
"value": "2.7-1",
"evidence": "/affected/2/versions"
},
{
"value": "2.7-2",
"evidence": "/affected/2/versions"
},
{
"value": "2.8.1-1",
"evidence": "/affected/2/versions"
},
{
"value": "2.8.3-1",
"evidence": "/affected/2/versions"
}
]
}
],
"severity": "high",
"structured": {
"id": "DEBIAN-CVE-2026-49476",
"aliases": [
"DEBIAN-CVE-2026-49476"
],
"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": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
}
]
}
],
"package": {
"name": "soupsieve",
"purl": "pkg:deb/debian/soupsieve?arch=source&distro=bookworm",
"ecosystem": "Debian:12"
},
"versions": [
"2.3.2-1",
"2.4-1",
"2.4.1-1",
"2.4.1-2",
"2.5-1",
"2.6-1",
"2.7-1",
"2.7-2",
"2.8.1-1",
"2.8.3-1",
"2.8.4-1"
],
"database_specific": {
"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-49476.json"
},
"ecosystem_specific": {
"urgency": "not yet assigned"
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
}
]
}
],
"package": {
"name": "soupsieve",
"purl": "pkg:deb/debian/soupsieve?arch=source&distro=trixie",
"ecosystem": "Debian:13"
},
"versions": [
"2.7-1",
"2.7-2",
"2.8.1-1",
"2.8.3-1",
"2.8.4-1"
],
"database_specific": {
"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-49476.json"
},
"ecosystem_specific": {
"urgency": "not yet assigned"
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "2.8.4-1"
}
]
}
],
"package": {
"name": "soupsieve",
"purl": "pkg:deb/debian/soupsieve?arch=source&distro=forky",
"ecosystem": "Debian:14"
},
"versions": [
"2.7-1",
"2.7-2",
"2.8.1-1",
"2.8.3-1"
],
"database_specific": {
"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-49476.json"
},
"ecosystem_specific": {
"urgency": "not yet assigned"
}
}
],
"modified": "2026-10-25T09:47:40.560882705Z",
"provider": "osv",
"upstream": [
"CVE-2026-49476"
],
"references": [
"https://security-tracker.debian.org/tracker/CVE-2026-49476"
]
},
"related_cves": [
{
"value": "CVE-2026-49476",
"evidence": "/upstream"
}
],
"security_relevant": true,
"severity_evidence": "/severity/0/score"
},
"source_id": "core-osv",
"document_id": 445166,
"published_at": "2026-07-14T21:17:01.877+00:00"
}