CVE-2020-5207

Request smuggling is possible in Ktor when both chunked TE and content length specified

Description

In Ktor before 1.3.0, request smuggling is possible when running behind a proxy that doesn't handle Content-Length and Transfer-Encoding properly or doesn't handle \n as a headers separator.

Category

5.4
CVSS
Severity: Medium
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.00%
Third-Party Advisory github.com Third-Party Advisory github.com
Affected: Ktor.io Ktor
Published at:
Updated at:

References

Link Tags
https://github.com/ktorio/ktor/security/advisories/GHSA-xrr9-rh8p-433v third party advisory
https://github.com/ktorio/ktor/pull/1547 third party advisory patch

Frequently Asked Questions

What is the severity of CVE-2020-5207?
CVE-2020-5207 has been scored as a medium severity vulnerability.
How to fix CVE-2020-5207?
To fix CVE-2020-5207, 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-2020-5207 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2020-5207 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-2020-5207?
CVE-2020-5207 affects Ktor.io Ktor.
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