modules/arch/win32/modisapi.c in modisapi in the Apache HTTP Server 2.0.37 through 2.0.63, 2.2.0 through 2.2.14, and 2.3.x before 2.3.7, when running on Windows, does not ensure that request processing is complete before calling isapiunload for an ISAPI .dll module, which allows remote attackers to execute arbitrary code via unspecified vectors related to a crafted request, a reset packet, and "orphaned callback pointers."

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

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

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.

An exploit was posted to full-disclosure labelled "Apache Killer". This script creates a number of threads that use multiple Range headers to exhaust memory on the Apache server.

The ASF httpd development team are working on a fix for this issue: http://www.gossamer-threads.com/lists/apache/dev/401638

Off-by-one error in the ldap scheme handling in the Rewrite module (modrewrite) in Apache 1.3 from 1.3.28, 2.0.46 and other versions before 2.0.59, and 2.2, when RewriteEngine is enabled, allows remote attackers to cause a denial of service (application crash) and possibly execute arbitrary code via crafted URLs that are not properly handled using certain rewrite rules.

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.

The Solaris pollset feature in the Event Port backend in poll/unix/port.c in the Apache Portable Runtime (APR) library before 1.3.9, as used in the Apache HTTP Server before 2.2.14 and other products, does not properly handle errors, which allows remote attackers to cause a denial of service (daemon hang) via unspecified HTTP requests, related to the prefork and event MPMs.

The expat XML parser in the aprxml interface in xml/aprxml.c in Apache APR-util before 1.3.7, as used in the moddav and moddavsvn modules in the Apache HTTP Server, allows remote attackers to cause a denial of service (memory consumption) via a crafted XML document containing a large number of nested entity references, as demonstrated by a PROPFIND request, a similar issue to CVE-2003-1564.

Martin Joey Schulze discovered a flaw in the way modauthmysql handles certain multibyte character encodings.

If modauthmysql is configured to use use a multibyte character set that allows the backslash '\' character as part of the character encodings, it is possible to inject arbitrary SQL commands to the MySQL database server.

An Uncontrolled Resource Consumption vulnerability in multiple products may allow an attacker to cause web service portal denial of service (DoS) via handling special crafted HTTP requests/responses in pieces slowly. Slow HTTP attacks are denial-of-service (DoS) attacks in which the attacker sends HTTP requests in pieces slowly, one at a time to a Web server. If an HTTP request is not complete, or if the transfer rate is very low, the server keeps its resources busy waiting for the rest of the data. When the server’s concurrent connection pool reaches its maximum, this creates a DoS. Slow HTTP attacks are easy to execute because they require only minimal resources from the attacker.

The streamreqbodycl function in modproxyhttp.c in the modproxy module in the Apache HTTP Server before 2.3.3, when a reverse proxy is configured, does not properly handle an amount of streamed data that exceeds the Content-Length value, which allows remote attackers to cause a denial of service (CPU consumption) via crafted requests.

François Guerraz reported in Debian BTS a possible DoS (CPU consumption) a DoS with moddeflate since it does not stop to compress large files even after the network connection has been closed. This allows to use large amounts of CPU if there is a largish file available that has moddeflate enabled.

Original report: http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=534712

Post to the apache-httpd-dev mailing list: http://marc.info/?l=apache-httpd-dev&m=124621326524824&w=2

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.

A single NULL byte buffer overflow flaw was found in apr-util's aprbrigadevprintf() function.

First let's assume the worst case and an attacker can control exactly what is being sent to aprbrigadevprintf and can trigger this issue by filling the buckets just right so you end up with one that is perfectly full as per the explanation at http://www.mail-archive.com/dev@apr.apache.org/msg21592.html

632 APUDECLARE(aprstatust) aprbrigadevprintf(aprbucketbrigade b, ... 638 struct brigadevprintfdatat vd; 639 char buf[APRBUCKETBUFFSIZE]; 640 aprsizet written; ... 656 (vd.vbuff.curpos) = '\0'; ... 659 return aprbrigadewrite(b, flush, ctx, buf, vd.vbuff.curpos - buf);

If we get to line 656 with vd.vbuff.curpos pointing to one past the end of buf we write a single NULL to the next thing on the stack after buf. And on the Linux x86 and x8664 builds we looked at this is actually the first byte of the vd structure, which is in fact the LSB of vd.vbuff.curpos itself.

So the only use of this after the overwrite is on line 659 where vd.vbuff.curpos gets used to calculate how much to write. Before the overwrite vd.vbuff.curpos was buf+APRBUCKETBUFFSIZE (8000), but now it could be between 0 and 255 bytes less. So aprbrigadewrite will end up writing out between 0 and 255 bytes less than it ought to, causing the truncation seen in the original bug report.

So for little endian systems it doesn't seem to have any security consequence. Of course for a big endian system aprbrigadewrite could end up dumping large amounts of memory (so an info disclosure leak or crash).

Cross-site scripting (XSS) vulnerability in modautoindex.c in the Apache HTTP Server before 2.2.6, when the charset on a server-generated page is not defined, allows remote attackers to inject arbitrary web script or HTML via the P parameter using the UTF-7 charset. NOTE: it could be argued that this issue is due to a design limitation of browsers that attempt to perform automatic content type detection.

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).

It was found that modrewrite writes data to a log file without sanitizing non-printable characters. A remote attacker could use this flaw to write terminal escape sequences to log files (if the RewriteLog directive was used by modrewrite). This could possibly cause arbitrary command execution, via HTTP requests containing an escape sequence for a terminal emulator. (if for example the log files were viewed in a terminal emulator)

Reference: http://svn.apache.org/viewvc?view=revision&revision=r1469311

Proposed patch: http://people.apache.org/~jorton/modrewrite-CVE-2013-1862.patch

Apache Portable Runtime (APR) is vulnerable to a denial of service, caused by an error in the aprfnmatch() function when processing specific patterns with the "" wildcard. A remote attacker could exploit this vulnerability to consume all available CPU and memory resources resulting in a denial of service.

The date handling code in modules/proxy/proxyutil.c (modproxy) in Apache 2.3.0, when using a threaded MPM, allows remote origin servers to cause a denial of service (caching forward proxy process crash) via crafted date headers that trigger a buffer over-read.

RMDG partner and independent security consultancy, "Context Information Security" has made CPNI Response aware of a security vulnerability which could potentially allow an attacker to gain full internal access to a network from the internet.

The technique exploits insecurely configured reverse web proxies to gain access to internal/DMZ systems.

This attack is based on an Apache web server which is using "modrewrite" to proxy web requests internally. Other proxies may suffer from this issue.

The vulnerability occurs if the Apache configuration file is configured like this:

RewriteRule ^(.) http://internalserver:80$1 [P]

As opposed to:

RewriteRule ^(.) http://internalserver:80/$1 [P]

It is important for readers to review their reverse proxy configurations to ensure that the rewrite rules are securely configured and cannot be abused in such a way that they can be used to compromise internal systems.

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

cacheutil.c in the modcache module in Apache HTTP Server (httpd), when caching is enabled and a threaded Multi-Processing Module (MPM) is used, allows remote attackers to cause a denial of service (child processing handler crash) via a request with the (1) s-maxage, (2) max-age, (3) min-fresh, or (4) max-stale Cache-Control headers without a value.

Apache HTTP Server 2.4.16 release fixes the following issue:

) SECURITY: CVE-2015-3183 (cve.mitre.org) core: Fix chunk header parsing defect. Remove aprbrigadeflatten(), buffering and duplicated code from the HTTPIN filter, parse chunks in a single pass with zero copy. Limit accepted chunk-size to 2^63-1 and be strict about chunk-ext authorized characters. [Graham Leggett, Yann Ylavic]

External References:

http://www.apache.org/dist/httpd/CHANGES2.4.16

The modproxyftp module in the Apache HTTP Server allows remote attackers to bypass intended access restrictions and send arbitrary commands to an FTP server via vectors related to the embedding of these commands in the Authorization HTTP header, as demonstrated by a certain module in VulnDisco Pack Professional 8.11. NOTE: as of 20090903, this disclosure has no actionable information. However, because the VulnDisco Pack author is a reliable researcher, the issue is being assigned a CVE identifier for tracking purposes.

References: http://intevydis.com/vd-list.shtml