Package Instance

Apache HTTP Server 2.4.65 and earlier with Server Side Includes (SSI) enabled and mod_cgid (but not mod_cgi) passes the shell-escaped query string to #exec cmd="..." directives.

This issue affects Apache HTTP Server before 2.4.66.

Users are recommended to upgrade to version 2.4.66, which fixes the issue.

HTTP response splitting in the core of Apache HTTP Server allows an attacker who can manipulate the Content-Type response headers of applications hosted or proxied by the server can split the HTTP response.

This vulnerability was described as CVE-2023-38709 but the patch included in Apache HTTP Server 2.4.59 did not address the issue.

Users are recommended to upgrade to version 2.4.64, which fixes this issue.

In some mod_ssl configurations on Apache HTTP Server versions through to 2.4.63, an HTTP desynchronisation attack allows a man-in-the-middle attacker to hijack an HTTP session via a TLS upgrade.

Only configurations using "SSLEngine optional" to enable TLS upgrades are affected. Users are recommended to upgrade to version 2.4.64, which removes support for TLS upgrade.

Server-Side Request Forgery (SSRF) in Apache HTTP Server on Windows allows to potentially leak NTLM hashes to a malicious server via 
mod_rewrite or apache expressions that pass unvalidated request input.

This issue affects Apache HTTP Server: from 2.4.0 through 2.4.63.

Note:  The Apache HTTP Server Project will be setting a higher bar for accepting vulnerability reports regarding SSRF via UNC paths. 

The server offers limited protection against administrators directing the server to open UNC paths.
Windows servers should limit the hosts they will connect over via SMB based on the nature of NTLM authentication.

Improper Neutralization of Escape, Meta, or Control Sequences vulnerability in Apache HTTP Server through environment variables set via the Apache configuration unexpectedly superseding variables calculated by the server for CGI programs.

This issue affects Apache HTTP Server from 2.4.0 through 2.4.65.

Users are recommended to upgrade to version 2.4.66 which fixes the issue.

Late Release of Memory after Effective Lifetime vulnerability in Apache HTTP Server.

This issue affects Apache HTTP Server: from 2.4.17 up to 2.4.63.

Users are recommended to upgrade to version 2.4.64, which fixes the issue.

In some mod_ssl configurations on Apache HTTP Server 2.4.35 through to 2.4.63, an access control bypass by trusted clients is possible using TLS 1.3 session resumption.

Configurations are affected when mod_ssl is configured for multiple virtual hosts, with each restricted to a different set of trusted client certificates (for example with a different SSLCACertificateFile/Path setting). In such a case, a client trusted to access one virtual host may be able to access another virtual host, if SSLStrictSNIVHostCheck is not enabled in either virtual host.

An integer overflow in the case of failed ACME certificate renewal leads, after a number of failures (~30 days in default configurations), to the backoff timer becoming 0. Attempts to renew the certificate then are repeated without delays until it succeeds.

This issue affects Apache HTTP Server: from 2.4.30 before 2.4.66.


Users are recommended to upgrade to version 2.4.66, which fixes the issue.

mod_userdir+suexec bypass via AllowOverride FileInfo vulnerability in Apache HTTP Server. Users with access to use the RequestHeader directive in htaccess can cause some CGI scripts to run under an unexpected userid.

This issue affects Apache HTTP Server: from 2.4.7 through 2.4.65.

Users are recommended to upgrade to version 2.4.66, which fixes the issue.

SSRF in Apache HTTP Server with mod_proxy loaded allows an attacker to send outbound proxy requests to a URL controlled by the attacker.  Requires an unlikely configuration where mod_headers is configured to modify the Content-Type request or response header with a value provided in the HTTP request.

Users are recommended to upgrade to version 2.4.64 which fixes this issue.

In certain proxy configurations, a denial of service attack against Apache HTTP Server versions 2.4.26 through to 2.4.63 can be triggered by untrusted clients causing an assertion in mod_proxy_http2.

Configurations affected are a reverse proxy is configured for an HTTP/2 backend, with ProxyPreserveHost set to "on".

Insufficient escaping of user-supplied data in mod_ssl in Apache HTTP Server 2.4.63 and earlier allows an untrusted SSL/TLS client to insert escape characters into log files in some configurations.

In a logging configuration where CustomLog is used with "%{varname}x" or "%{varname}c" to log variables provided by mod_ssl such as SSL_TLS_SNI, no escaping is performed by either mod_log_config or mod_ssl and unsanitized data provided by the client may appear in log files.