CVE-2020-5207 MEDIUM

CVE-2020-5207: Request smuggling is possible in Ktor when both chunked TE and content length specified

Vendor Ktor.io

Product Ktor

Weakness CWE-444

Published January 27, 2020

Last update August 4, 2024

View on NVD All CVEs

CVSS base score

5.4/10

Attack vector Network

Attack complexity Low

Privileges required Low

User interaction Required

Confidentiality Low

Integrity Low

CVSS vector

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

What the vulnerability does

01Description

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.

Key dates

02Disclosure timeline

January 27, 2020 CVE published

August 4, 2024 Record updated

External resources

03References

NVD — National Vulnerability Database https://nvd.nist.gov/vuln/detail/CVE-2020-5207 CWE — Common Weakness Enumeration https://cwe.mitre.org/data/definitions/444.html

Related vulnerabilities

04Related CVE

CVE-2026-11541 IBM WebSphere Application Server and WebSphere Application Server Liberty are affected by HTTP request smuggling CVE-2020-5218 Ability in Sylius to switch channels via GET parameter enabled in production environments CVE-2023-38697 protocol-http1 HTTP Request/Response Smuggling vulnerability CVE-2025-6442 Ruby WEBrick read_header HTTP Request Smuggling Vulnerability CVE-2026-42585 Netty: HTTP Request Smuggling due to malformed Transfer-Encoding