CVE-2023-25577
This allows an attacker to cause a denial of service by sending crafted multipart data to an endpoint that will parse it.
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (1.42%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
Description
Werkzeug is a comprehensive WSGI web application library. Prior to version 2.2.3, Werkzeug's multipart form data parser will parse an unlimited number of parts, including file parts. Parts can be a small amount of bytes, but each requires CPU time to parse and may use more memory as Python data. If a request can be made to an endpoint that accesses `request.data`, `request.form`, `request.files`, or `request.get_data(parse_form_data=False)`, it can cause unexpectedly high resource usage. 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. The amount of RAM required can trigger an out of memory kill of the process. Unlimited file parts can use up memory and file handles. If many concurrent requests are sent continuously, this can exhaust or kill all available workers. Version 2.2.3 contains a patch for this issue.
- CVSS 3.1
- 7.5 HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
- EPSS
- 1.42% probability · 73th percentile
- Public exploits
- None in Exploit-DB
- CISA KEV
- Not listed
- Weakness
- CWE-770
- Affected
- palletsprojects/werkzeug
- Source
- security-advisories@github.com
EPSS 1.4% since 26 October 2026; no change recorded yet. Points are recorded when the score first appears and whenever it moves by a percentage point or more.
References
- https://github.com/pallets/werkzeug/commit/517cac5a804e8c4dc4ed038bb20dacd038e7a9f1Patch
- https://github.com/pallets/werkzeug/releases/tag/2.2.3Release Notes
- https://github.com/pallets/werkzeug/security/advisories/GHSA-xg9f-g7g7-2323Vendor Advisory
- https://security.netapp.com/advisory/ntap-20230818-0003/
- https://www.debian.org/security/2023/dsa-5470
- https://github.com/pallets/werkzeug/commit/517cac5a804e8c4dc4ed038bb20dacd038e7a9f1Patch
- https://github.com/pallets/werkzeug/releases/tag/2.2.3Release Notes
- https://github.com/pallets/werkzeug/security/advisories/GHSA-xg9f-g7g7-2323Vendor Advisory
- https://security.netapp.com/advisory/ntap-20230818-0003/
- https://www.debian.org/security/2023/dsa-5470
Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.