modsecurity-crs — security advisory
The OWASP ModSecurity Core Rule Set (CRS) is affected by a partial rule set bypass for HTTP multipart requests by submitting a payload that uses a character encoding scheme via the Content-Type or the deprecated Content-Transfer-Encoding multipart MIME header fields that will not be decoded and inspected by the web application firewall engine and the rule set. The multipart payload will therefore bypass detection. A vulnerable backend that supports these encoding schemes can potentially be exploited. The legacy CRS versions 3.0.x and 3.1.x are affected, as well as the currently supported versions 3.2.1 and 3.3.2. Integrators and users are advised upgrade to 3.2.2 and 3.3.3 respectively. The mitigation against these vulnerabilities depends on the installation of the latest ModSecurity version (v2.9.6 / v3.0.8).
- Products
- modsecurity-crs
- Affected versions
- Not specified
- Fixed versions
- 3.3.4-1
- CVEs
- CVE-2022-39956
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 30 Oct 2026, 14:58 UTC · Revision 1
Source evidence
The OWASP ModSecurity Core Rule Set (CRS) is affected by a partial rule set bypass for HTTP multipart requests by submitting a payload that uses a character encoding scheme via the Content-Type or the deprecated Content-Transfer-Encoding multipart MIME header fields that will not be decoded and inspected by the web application firewall engine and the rule set. The multipart payload will therefore bypass detection. A vulnerable backend that supports these encoding schemes can potentially be exploited. The legacy CRS versions 3.0.x and 3.1.x are affected, as well as the currently supported versions 3.2.1 and 3.3.2. Integrators and users are advised upgrade to 3.2.2 and 3.3.3 respectively. The mitigation against these vulnerabilities depends on the installation of the latest ModSecurity version (v2.9.6 / v3.0.8).
osv:DEBIAN-CVE-2022-39956
modsecurity-crs
Fixed versions: 3.3.4-1
modsecurity-crs
Fixed versions: 3.3.4-1
modsecurity-crs
Fixed versions: 3.3.4-1
Complete source record
{
"id": "7eba2199026ed350328be857defa04fc7389478b7687c15019e29c3e86da68e9",
"url": "https://osv.dev/vulnerability/DEBIAN-CVE-2022-39956",
"method": "structured",
"payload": {
"kind": "advisory",
"title": "DEBIAN-CVE-2022-39956",
"summary": "The OWASP ModSecurity Core Rule Set (CRS) is affected by a partial rule set bypass for HTTP multipart requests by submitting a payload that uses a character encoding scheme via the Content-Type or the deprecated Content-Transfer-Encoding multipart MIME header fields that will not be decoded and inspected by the web application firewall engine and the rule set. The multipart payload will therefore bypass detection. A vulnerable backend that supports these encoding schemes can potentially be exploited. The legacy CRS versions 3.0.x and 3.1.x are affected, as well as the currently supported versions 3.2.1 and 3.3.2. Integrators and users are advised upgrade to 3.2.2 and 3.3.3 respectively. The mitigation against these vulnerabilities depends on the installation of the latest ModSecurity version (v2.9.6 / v3.0.8).",
"evidence": "osv:DEBIAN-CVE-2022-39956",
"products": [
{
"name": {
"value": "modsecurity-crs",
"evidence": "/affected/0/package/name"
},
"prerequisites": [],
"fixed_versions": [
{
"value": "3.3.4-1",
"evidence": "/affected/0/ranges"
}
],
"affected_versions": []
},
{
"name": {
"value": "modsecurity-crs",
"evidence": "/affected/1/package/name"
},
"prerequisites": [],
"fixed_versions": [
{
"value": "3.3.4-1",
"evidence": "/affected/1/ranges"
}
],
"affected_versions": []
},
{
"name": {
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"evidence": "/affected/2/package/name"
},
"prerequisites": [],
"fixed_versions": [
{
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"evidence": "/affected/2/ranges"
}
],
"affected_versions": []
}
],
"severity": "critical",
"structured": {
"id": "DEBIAN-CVE-2022-39956",
"aliases": [
"DEBIAN-CVE-2022-39956"
],
"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": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "3.3.4-1"
}
]
}
],
"package": {
"name": "modsecurity-crs",
"purl": "pkg:deb/debian/modsecurity-crs?arch=source&distro=bookworm",
"ecosystem": "Debian:12"
},
"database_specific": {
"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2022-39956.json"
},
"ecosystem_specific": {
"urgency": "not yet assigned"
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "3.3.4-1"
}
]
}
],
"package": {
"name": "modsecurity-crs",
"purl": "pkg:deb/debian/modsecurity-crs?arch=source&distro=trixie",
"ecosystem": "Debian:13"
},
"database_specific": {
"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2022-39956.json"
},
"ecosystem_specific": {
"urgency": "not yet assigned"
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "3.3.4-1"
}
]
}
],
"package": {
"name": "modsecurity-crs",
"purl": "pkg:deb/debian/modsecurity-crs?arch=source&distro=forky",
"ecosystem": "Debian:14"
},
"database_specific": {
"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2022-39956.json"
},
"ecosystem_specific": {
"urgency": "not yet assigned"
}
}
],
"modified": "2026-10-15T08:02:41.485541102Z",
"provider": "osv",
"upstream": [
"CVE-2022-39956"
],
"references": [
"https://security-tracker.debian.org/tracker/CVE-2022-39956"
]
},
"related_cves": [
{
"value": "CVE-2022-39956",
"evidence": "/upstream"
}
],
"security_relevant": true,
"severity_evidence": "/severity/0/score"
},
"source_id": "core-osv",
"document_id": 323980,
"published_at": "2022-09-20T07:15:12.293+00:00"
}