CVE-2024-49768

Description

Waitress is a Web Server Gateway Interface server for Python 2 and 3. A remote client may send a request that is exactly recv_bytes (defaults to 8192) long, followed by a secondary request using HTTP pipelining. When request lookahead is disabled (default) we won't read any more requests, and when the first request fails due to a parsing error, we simply close the connection. However when request lookahead is enabled, it is possible to process and receive the first request, start sending the error message back to the client while we read the next request and queue it. This will allow the secondary request to be serviced by the worker thread while the connection should be closed. Waitress 3.0.1 fixes the race condition. As a workaround, disable channel_request_lookahead, this is set to 0 by default disabling this feature.

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CVSS v3.1 Score

9.1

CRITICAL

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N

Weakness Type (CWE)

CWE-367 CWE-367

CWE-444 CWE-444

Affected Products

Vendor	Product	Versions
agendaless	waitress	2.0.0 — 3.0.1

References

Advisories & Patches

https://github.com/Pylons/waitress/commit/e4359018537af376cf24bd13616d861e2fb76f65 https://github.com/Pylons/waitress/security/advisories/GHSA-9298-4cf8-g4wj

Frequently Asked Questions

What is CVE-2024-49768? +

Waitress is a Web Server Gateway Interface server for Python 2 and 3. A remote client may send a request that is exactly recv_bytes (defaults to 8192) long, followed by a secondary request using HTTP pipelining. When request lookahead is disabled (default) we won't read any more requests, and when the first request fails due to a parsing error, we simply close the connection. However when request lookahead is enabled, it is possible to process and receive the first request, start sending the error message back to the client while we read the next request and queue it. This will allow the secondary request to be serviced by the worker thread while the connection should be closed. Waitress 3.0.1 fixes the race condition. As a workaround, disable channel_request_lookahead, this is set to 0 by default disabling this feature. It has a CVSS v3.1 base score of 9.1 (CRITICAL).

How severe is CVE-2024-49768? +

CVE-2024-49768 has a CVSS v3.1 score of 9.1 out of 10, rated CRITICAL. This is a critical vulnerability that should be patched immediately.

What products are affected by CVE-2024-49768? +

CVE-2024-49768 affects products from agendaless, specifically: waitress. Check the affected products table above for specific version ranges.

How do I check if I'm vulnerable to CVE-2024-49768? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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