CVE-2025-59822— Http4s vulnerable to HTTP Request Smuggling due to improper handling of HTTP trailer section
Quick assessment
Affected
http4s http4s
Exploitation
No confirmed in-the-wild exploitation; assess based on exposure
Recommended action
Check the vendor advisory and references for a fixed version. If immediate upgrade is impossible, restrict exposure and increase monitoring.
Http4s是Http4s开源的一款开源的用于Scala的流HTTP服务器。 Http4s 1.0.0-M1版本至1.0.0-M45之前版本和0.23.31之前版本存在安全漏洞，该漏洞源于HTTP trailer部分处理不当，可能导致HTTP请求夹带技术攻击。
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I. Basic Information for CVE-2025-59822
Vulnerability Information
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Vulnerability Title
Http4s vulnerable to HTTP Request Smuggling due to improper handling of HTTP trailer section
Source: CVE Program / CVE List V5
Vulnerability Description
Http4s is a Scala interface for HTTP services. In versions from 1.0.0-M1 to before 1.0.0-M45 and before 0.23.31, http4s is vulnerable to HTTP Request Smuggling due to improper handling of HTTP trailer section. This vulnerability could enable attackers to bypass front-end servers security controls, launch targeted attacks against active users, and poison web caches. A pre-requisite for exploitation involves the web application being deployed behind a reverse-proxy that forwards trailer headers. This issue has been patched in versions 1.0.0-M45 and 0.23.31.
Source: CVE Program / CVE List V5
CVSS Information
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N
Source: CVE Program / CVE List V5
Vulnerability Type
HTTP请求的解释不一致性(HTTP请求私运)
Source: CVE Program / CVE List V5
Vulnerability Title
Http4s 安全漏洞
Source: CNNVD (China National Vulnerability Database)
Vulnerability Description
Http4s是Http4s开源的一款开源的用于Scala的流HTTP服务器。 Http4s 1.0.0-M1版本至1.0.0-M45之前版本和0.23.31之前版本存在安全漏洞，该漏洞源于HTTP trailer部分处理不当，可能导致HTTP请求夹带技术攻击。
Source: CNNVD (China National Vulnerability Database)
CVSS Information
N/A
Source: CNNVD (China National Vulnerability Database)
Vulnerability Type
N/A
Source: CNNVD (China National Vulnerability Database)
Affected Products
II. Public POCs for CVE-2025-59822
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Vendor Advisories for CVE-2025-59822 (1)
IV. Related Vulnerabilities
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Same weakness: CWE-444
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V. Comments for CVE-2025-59822
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