CVE-2023-25577

What it is

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.

At a glance

Exploitability

Can be exploited over the network without logging in. High risk of service disruption.

Exploit odds

1.4% chance of exploitation in the next 30 days (EPSS).

Fix

A patch, advisory or fixed version is referenced. Upgrade or apply it.

Timeline

1. 2023-02-14 20:15 UTC PublishedDisclosed publicly on CVE.org and NVD
2. 2026-06-17 05:41 UTC Last updatedMost recent change to the record

Why it ranks here

• Exploited in the wild: no, CISA does not list it.
• Exploit odds: 1.4% in the next 30 days (EPSS).
• Severity: 7.5 HIGH (CVSS).
• Fix: a patch or advisory is linked.

Details

Published

2023-02-14 20:15 UTC

Last modified

2026-06-17 05:41 UTC

Exploit probability

1.4% · EPSS, next 30 days

Weakness

CWE-770 · Allocation without limits

Record status

Modified

Affected

• Palletsprojects Werkzeug < 2.2.3

Attack profile CVSS 3.1 · 7.5

Attack vector

Network

Complexity

Low

Privileges needed

None

User interaction

None

Scope

Unchanged

Confidentiality

None

Integrity

None

Availability

High

Is it in your code?

Hand this to your coding agent. It searches your project for the affected products and checks versions. Nothing leaves your machine.

Read https://cve-list.com/agent/cve/CVE-2023-25577.md and follow it. Check whether this project is affected by CVE-2023-25577. Read only. Don't change anything and don't upload my code. Tell me yes, no or not sure, with the file as proof.

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