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Advisory details: ubuntu_osv / UBUNTU-CVE-2022-39956
Advisory ID ubuntu_osv/UBUNTU-CVE-2022-39956
Aliases 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).
Status Published
Exploitability 0.5
Weighted Severity 8.8
Risk 4.4
Affected and Fixed Packages Package Details
Introduced and Fixed Package Commit Patches Package Commit Patches Details
Weaknesses (0)
There are no known CWE.
System Score Found at
cvssv3.1 7.3 https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2022/UBUNTU-CVE-2022-39956.json
cvssv3.1 9.8 https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2022/UBUNTU-CVE-2022-39956.json
ubuntu-priority low https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2022/UBUNTU-CVE-2022-39956.json
Reference id Reference type URL
https://bugs.debian.org/1020303
https://ubuntu.com/security/CVE-2022-39956
https://www.cve.org/CVERecord?id=CVE-2022-39956
crs-version-3-3-3-and-3-2-2-covering-several-cves Other https://coreruleset.org/20220919/crs-version-3-3-3-and-3-2-2-covering-several-cves/
No exploits are available.

No EPSS data available for this advisory.

Patch URL
There are no known patches.
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L Found at https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2022/UBUNTU-CVE-2022-39956.json
Attack Vector (AV) Attack Complexity (AC) Privileges Required (PR) User Interaction (UI) Scope (S) Confidentiality Impact (C) Integrity Impact (I) Availability Impact (A)

network

adjacent_network

local

physical

low

high

none

low

high

none

required

unchanged

changed

high

low

none

high

low

none

high

low

none
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H Found at https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2022/UBUNTU-CVE-2022-39956.json
Attack Vector (AV) Attack Complexity (AC) Privileges Required (PR) User Interaction (UI) Scope (S) Confidentiality Impact (C) Integrity Impact (I) Availability Impact (A)

network

adjacent_network

local

physical

low

high

none

low

high

none

required

unchanged

changed

high

low

none

high

low

none

high

low

none

There are no SSVC decisions available.