CVE-2021-39214

Lacking Protection against HTTP Request Smuggling in mitmproxy

Description

mitmproxy is an interactive, SSL/TLS-capable intercepting proxy. In mitmproxy 7.0.2 and below, a malicious client or server is able to perform HTTP request smuggling attacks through mitmproxy. This means that a malicious client/server could smuggle a request/response through mitmproxy as part of another request/response's HTTP message body. While a smuggled request is still captured as part of another request's body, it does not appear in the request list and does not go through the usual mitmproxy event hooks, where users may have implemented custom access control checks or input sanitization. Unless one uses mitmproxy to protect an HTTP/1 service, no action is required. The vulnerability has been fixed in mitmproxy 7.0.3 and above.

Category

8.1
CVSS
Severity: High
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.19%
Third-Party Advisory github.com
Affected: mitmproxy mitmproxy
Published at:
Updated at:

References

Frequently Asked Questions

What is the severity of CVE-2021-39214?
CVE-2021-39214 has been scored as a high severity vulnerability.
How to fix CVE-2021-39214?
To fix CVE-2021-39214, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2021-39214 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2021-39214 is being actively exploited. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-39214?
CVE-2021-39214 affects mitmproxy mitmproxy.
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