CVE-2023-46136
Werkzeug DoS: High resource usage when parsing multipart/form-data containing a large part with CR/LF character at the beginning
Description
Werkzeug is a comprehensive WSGI web application library. 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.
How to fix CVE-2023-46136
To remediate CVE-2023-46136, upgrade the affected package to a fixed version below.
- —upgrade to 2.3.7-r0 or later
- —upgrade to 2.2.2-3+deb12u1 or later
- —upgrade to 3.0.1 or later
- —upgrade to f3c803b3ade485a45f12b6d6617595350c0f03e2 or later
Is CVE-2023-46136 being exploited?
Low — EPSS is 0.9%, meaning exploitation activity has not been observed at scale.
Affected packages (4)
- from 0, < 2.3.7-r0
- from 0, < 2.2.2-3+deb12u1
- >= 3.0.0, < 3.0.1
- from 0, < f3c803b3ade485a45f12b6d6617595350c0f03e2, < f2300208d5e2a5076cbbb4c2aad71096fd040ef9 | from 0, < 2.3.8, >= 3.0.0, < 3.0.1
CVSS scores
| Source | Version | Severity | Vector |
|---|---|---|---|
| osv | CVSS 3.1 | MEDIUM5.7 | CVSS:3.1/AV:A/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H |