Werkzeug is a comprehensive WSGI web application library. In versions on the 3.x branch prior to 3.0.1 and on the 2.x branch prior to 2.3.8, if an upload of a file that starts with CR or LF and then is followed by megabytes of data without these characters: all of these bytes are appended chunk by chunk into internal bytearray and lookup for boundary is performed on growing buffer. This allows an attacker to cause a denial of service by sending crafted multipart data to an endpoint that will parse it. The amount of CPU time required can block worker processes from handling legitimate requests. This vulnerability has been patched in version 3.0.1 and 2.3.8.
CVSS Details
- CVSS 3.1 Base Score: 8
- CVSS 3.1 Vector: (CVSS:3.1/AV:A/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H)
Covered by Rapid7
| Product | Vendor Advisory | Solution File | Added | Published |
|---|---|---|---|---|
| Alpine Linux | alpine-linux-upgrade-py3-werkzeug | Aug 22, 2024 | Oct 24, 2023 | |
| Debian | debian-upgrade-python-werkzeug | Jan 13, 2025 | Oct 25, 2023 | |
| Redhat Openshift | linuxrpm-upgrade-python-werkzeug | Nov 30, 2023 | Oct 25, 2023 | |
| Redhat_linux | — | no-fix-redhat-rpm-package | Jul 9, 2025 | Oct 25, 2023 |
| Suse | — | suse-upgrade-python311-werkzeug | Nov 1, 2023 | Oct 25, 2023 |
| Vmware Photon_os | vmware-photon_os_update_tdnf | Jul 2, 2025 | Oct 24, 2023 |
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