CVE-2016-5387
HighSummary
Apache HTTP Server through 2.4.23 does not protect applications from untrusted client data in the HTTP_PROXY environment variable, allowing remote attackers to redirect an application's outbound HTTP traffic to an arbitrary proxy server via a crafted Proxy header in an HTTP request.
Risk Assessment
Attackers could exploit this vulnerability to intercept or manipulate an application's outbound traffic, posing a significant threat to the organization's data security.
Recommendation
It is recommended to update the Apache HTTP Server to version 2.4.24 or later and to monitor and filter Proxy headers in incoming HTTP requests.
Other vulnerabilities in Apache HTTP Server
See all- CVE-2017-9798High
Apache httpd allows remote attackers to read secret data from process memory if the Limit directive can be set in a user's .htaccess file, or if httpd.conf has certain misconfigurations. This affects the Apache HTTP Server through 2.2.34 and 2.4.x through 2.4.27.
- CVE-2016-8743High
Apache HTTP Server, in all releases prior to 2.2.32 and 2.4.25, was liberal in the whitespace accepted from requests and sent in response lines and headers. This acceptance of different behaviors represented a security concern when httpd participates in any chain of proxies or interacts with back-end application servers.
- CVE-2016-4979High
Apache HTTP Server versions 2.4.18 to 2.4.20, when mod_http2 and mod_ssl are enabled, improperly recognize the 'SSLVerifyClient require' directive for HTTP/2 request authorization. This allows remote attackers to bypass intended access restrictions.
- CVE-2024-38475High
Improper escaping of output in mod_rewrite in Apache HTTP Server 2.4.59 and earlier allows an attacker to map URLs to filesystem locations that are permitted to be served but not directly reachable, leading to code execution or source code disclosure.
- CVE-2024-38477Medium
Null pointer dereference in mod_proxy in Apache HTTP Server 2.4.59 and earlier allows an attacker to crash the server via a malicious request.
- CVE-2023-38709Medium
Faulty input validation in the core of Apache HTTP Server through 2.4.58 allows malicious or exploitable backend/content generators to split HTTP responses, leading to HTTP response splitting attacks.
- CVE-2024-24795Medium
HTTP Response splitting in multiple modules in Apache HTTP Server allows an attacker that can inject malicious response headers into backend applications to cause an HTTP desynchronization attack.
- CVE-2024-40725Medium
A partial fix for CVE-2024-39884 in Apache HTTP Server 2.4.61 ignores some legacy content-type based configurations like AddType. Under certain circumstances with indirect file requests, this can lead to source code disclosure of local content.
- CVE-2024-36387Medium
Serving WebSocket protocol upgrades over an HTTP/2 connection could result in a Null Pointer dereference, leading to a crash of the server process, degrading performance.
- CVE-2024-27316Medium
HTTP/2 incoming headers exceeding the limit are temporarily buffered in nghttp2 to generate an informative HTTP 413 response. If a client does not stop sending headers, this leads to memory exhaustion.
Original NVD description (English source)
The Apache HTTP Server through 2.4.23 follows RFC 3875 section 4.1.18 and therefore does not protect applications from the presence of untrusted client data in the HTTP_PROXY environment variable, which might allow remote attackers to redirect an application's outbound HTTP traffic to an arbitrary proxy server via a crafted Proxy header in an HTTP request, aka an "httpoxy" issue. NOTE: the vendor states "This mitigation has been assigned the identifier CVE-2016-5387"; in other words, this is not a CVE ID for a vulnerability.