In Apache httpd 2.2.0 to 2.4.29, when generating an HTTP Digest authentication challenge, the nonce sent to prevent reply attacks was not correctly generated using a pseudo-random seed. In a cluster of servers using a common Digest authentication configuration, HTTP requests could be replayed across servers by an attacker without detection.

apache. Multiple issues were addressed by updating to version 2.4.27.

apache. Multiple issues existed in Apache. These were addressed by updating Apache to version 2.4.25.

In Apache httpd 2.0.23 to 2.0.65, 2.2.0 to 2.2.34, and 2.4.0 to 2.4.29, modauthnzldap, if configured with AuthLDAPCharsetConfig, uses the Accept-Language header value to lookup the right charset encoding when verifying the user's credentials. If the header value is not present in the charset conversion table, a fallback mechanism is used to truncate it to a two characters value to allow a quick retry (for example, 'en-US' is truncated to 'en'). A header value of less than two characters forces an out of bound write of one NUL byte to a memory location that is not part of the string. In the worst case, quite unlikely, the process would crash which could be used as a Denial of Service attack. In the more likely case, this memory is already reserved for future use and the issue has no effect at all.

apache. Multiple issues existed in Apache. These were addressed by updating Apache to version 2.4.25.

apache. Multiple issues existed in Apache. These were addressed by updating Apache to version 2.4.25.

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. Accepting these different behaviors represented a security concern when httpd participates in any chain of proxies or interacts with back-end application servers, either through modproxy or using conventional CGI mechanisms, and may result in request smuggling, response splitting and cache pollution.

A use-after free vulnerability was found in apache httpd. There's an apache configuration directive <Limit> that can be used to restrict access to certain HTTP methods. If one sets this inside an .htaccess file with an HTTP method that's not registered in the server the bug happens (e.g. set <Limit INVALID></Limit> in .htaccess). The reason is that at that point the variables used to build up the "Allow" header have already been freed, as it's not expecting any more changes to it.

Note that the bug only appears with OPTIONS requests to a specific path, not with "" OPTIONS requests.

An attacker on a shared hosting could could deliberately create an .htaccess file triggering the bug and subsequently try to exfiltrate data pieces from the global apache process that may contain secrets like password hashes.

Upstream patch:

https://svn.apache.org/viewvc?view=revision&revision=1807754

modsessiondbd.c in the modsessiondbd module in the Apache HTTP Server before 2.4.5 proceeds with save operations for a session without considering the dirty flag and the requirement for a new session ID, which has unspecified impact and remote attack vectors.

envvars (aka envvars-std) in the Apache HTTP Server before 2.4.2 places a zero-length directory name in the LDLIBRARYPATH, which allows local users to gain privileges via a Trojan horse DSO in the current working directory during execution of apachectl.

Race condition in the modstatus module in the Apache HTTP Server before 2.4.10 allows remote attackers to cause a denial of service (heap-based buffer overflow), or possibly obtain sensitive credential information or execute arbitrary code, via a crafted request that triggers improper scoreboard handling within the statushandler function in modules/generators/modstatus.c and the luaapscoreboardworker function in modules/lua/luarequest.c.

Possible CRLF injection allowing HTTP response splitting attacks for sites which use moduserdir. This issue was mitigated by changes made in 2.4.25 and 2.2.32 which prohibit CR or LF injection into the "Location" or other outbound header key or value. Fixed in Apache HTTP Server 2.4.25 (Affected 2.4.1-2.4.23). Fixed in Apache HTTP Server 2.2.32 (Affected 2.2.0-2.2.31).

IP address spoofing when proxying using modremoteip and modrewrite For configurations using proxying with modremoteip and certain modrewrite rules, an attacker could spoof their IP address for logging and PHP scripts. Note this issue was fixed in Apache HTTP Server 2.4.24 but was retrospectively allocated a low severity CVE in 2020.

Memory leak in the winntaccept function in server/mpm/winnt/child.c in the WinNT MPM in the Apache HTTP Server 2.4.x before 2.4.10 on Windows, when the default AcceptFilter is enabled, allows remote attackers to cause a denial of service (memory consumption) via crafted requests.

Martin Holst Swende discovered a flaw in the way modheaders handled chunked requests. A remote attacker could use this flaw to bypass intended modheaders restrictions, allowing them to send requests to applications that include headers that should have been removed by modheaders.

Discussion and a possible patch is available from the following thread:

http://marc.info/?t=138219209900002&r=1&w=2

References:

http://martin.swende.se/blog/HTTPChunked.html

The davxmlgetcdata function in main/util.c in the moddav module in the Apache HTTP Server before 2.4.8 does not properly remove whitespace characters from CDATA sections, which allows remote attackers to cause a denial of service (daemon crash) via a crafted DAV WRITE request.

The logcookie function in modlogconfig.c in the modlogconfig module in the Apache HTTP Server before 2.4.8 allows remote attackers to cause a denial of service (segmentation fault and daemon crash) via a crafted cookie that is not properly handled during truncation.

The following flaw has been fixed in the Apache HTTP Server:

"A flaw was found in modcgid. If a server using modcgid hosted CGI scripts which did not consume standard input, a remote attacker could cause child processes to hang indefinitely, leading to denial of service."

External References:

http://httpd.apache.org/security/vulnerabilities24.html

It was reported that if Content-Type header value is empty, httpd with modcache enabled will segfault: https://issues.apache.org/bugzilla/showbug.cgi?id=56924

Upstream patch: http://svn.apache.org/viewvc?view=revision&revision=1624234

modauthzsvn in Apache Subversion 1.7.x before 1.7.21 and 1.8.x before 1.8.14, when using Apache httpd 2.4.x, does not properly restrict anonymous access, which allows remote anonymous users to read hidden files via the path name.

The proxy functionality in (1) modproxyajp.c in the modproxyajp module and (2) modproxyhttp.c in the modproxyhttp module in the Apache HTTP Server 2.4.x before 2.4.3 does not properly determine the situations that require closing a back-end connection, which allows remote attackers to obtain sensitive information in opportunistic circumstances by reading a response that was intended for a different client.

moddav.c in the Apache HTTP Server before 2.2.25 does not properly determine whether DAV is enabled for a URI, which allows remote attackers to cause a denial of service (segmentation fault) via a MERGE request in which the URI is configured for handling by the moddavsvn module, but a certain href attribute in XML data refers to a non-DAV URI.

The deflateinfilter function in moddeflate.c in the moddeflate module in the Apache HTTP Server before 2.4.10, when request body decompression is enabled, allows remote attackers to cause a denial of service (resource consumption) via crafted request data that decompresses to a much larger size.

If an authorization script for LuaAuthzProvider were provided in the configuration multiple times, only the arguments of the last specification were used when invoking the script. This could lead to scripts being invoked with unexpected arguments.

Further details are available in the thread of the original report and bug:

http://www.openwall.com/lists/oss-security/2014/11/28/5

https://issues.apache.org/bugzilla/showbug.cgi?id=57204

Upstream fix:

https://github.com/apache/httpd/commit/3f1693d558d0758f829c8b53993f1749ddf6ffcb

This affects Apache HTTP Server versions 2.3 and later (such as what is shipped in Red Hat Enterprise Linux 7), as modlua is not available in earlier releases. Note that support for LuaAuthzProvider is experimental.

Cross-site scripting (XSS) vulnerability in the modnegotiation module in the Apache HTTP Server 2.2.6 and earlier in the 2.2.x series, 2.0.61 and earlier in the 2.0.x series, and 1.3.39 and earlier in the 1.3.x series allows remote authenticated users to inject arbitrary web script or HTML by uploading a file with a name containing XSS sequences and a file extension, which leads to injection within a (1) "406 Not Acceptable" or (2) "300 Multiple Choices" HTTP response when the extension is omitted in a request for the file.

Common Vulnerabilities and Exposures assigned an identifier CVE-2012-4558 tothe following vulnerability:

Name: CVE-2012-4558 URL: http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2012-4558 Assigned: 20120821 Reference: http://httpd.apache.org/security/vulnerabilities22.html Reference: http://httpd.apache.org/security/vulnerabilities24.html Reference: http://svn.apache.org/viewvc/httpd/httpd/trunk/modules/proxy/modproxybalancer.c?r1=1404653&r2=1413732&diffformat=h

Multiple cross-site scripting (XSS) vulnerabilities in the balancerhandler function in the manager interface in modproxybalancer.c in the modproxybalancer module in the Apache HTTP Server 2.2.x before 2.2.24-dev and 2.4.x before 2.4.4 allow remote attackers to inject arbitrary web script or HTML via a crafted string.

Common Vulnerabilities and Exposures assigned an identifier CVE-2012-3499 to the following vulnerability:

Name: CVE-2012-3499 URL: http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2012-3499 Assigned: 20120614 Reference: http://httpd.apache.org/security/vulnerabilities22.html Reference: http://httpd.apache.org/security/vulnerabilities24.html Reference: http://svn.apache.org/viewvc/httpd/httpd/trunk/modules/generators/modinfo.c?r1=1225799&r2=1413732&diffformat=h Reference: http://svn.apache.org/viewvc/httpd/httpd/trunk/modules/generators/modstatus.c?r1=1389564&r2=1413732&diffformat=h Reference: http://svn.apache.org/viewvc/httpd/httpd/trunk/modules/ldap/utilldapcachemgr.c?r1=1209766&r2=1418752&diffformat=h Reference: http://svn.apache.org/viewvc/httpd/httpd/trunk/modules/mappers/modimagemap.c?r1=1398480&r2=1413732&diffformat=h Reference: http://svn.apache.org/viewvc/httpd/httpd/trunk/modules/proxy/modproxyftp.c?r1=1404625&r2=1413732&diffformat=h

Multiple cross-site scripting (XSS) vulnerabilities in the Apache HTTP Server 2.2.x before 2.2.24-dev and 2.4.x before 2.4.4 allow remote attackers to inject arbitrary web script or HTML via vectors involving hostnames and URIs in the (1) modimagemap, (2) modinfo, (3) modldap, (4) modproxyftp, and (5) modstatus modules.

Apache HTTP Server 2.4.16 release fixes the following issue:

) SECURITY: CVE-2015-3185 (cve.mitre.org) Replacement of apsomeauthrequired (unusable in Apache httpd 2.4) with new apsomeauthnrequired and apforceauthn hook. [Ben Reser]

External References:

http://httpd.apache.org/security/vulnerabilities24.html#2.4.16

Multiple cross-site scripting (XSS) vulnerabilities in the makevariantlist function in modnegotiation.c in the modnegotiation module in the Apache HTTP Server 2.4.x before 2.4.3, when the MultiViews option is enabled, allow remote attackers to inject arbitrary web script or HTML via a crafted filename that is not properly handled during construction of a variant list.