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).

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

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.

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.

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

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.

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.

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

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.

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.

A flaw was found in the default error response for status code 400. This could be used by an attacker to expose "httpOnly" cookies, when no custom ErrorDocument was specified.

This affects all versions of Apache from 2.2.0 up to and including 2.2.21. It will be fixed upstream in 2.2.22 (via r1235454 [1]).

[1] http://svn.apache.org/viewvc?view=revision&revision=1235454

Apache 2.2 fixed a possible crash on shutdown if a child changes the sbtype field in the scoreboard. Since unprivileged children should not be able to affect the parent in this way, this is treated as a Low severity security issue [1].

The reporter has a nice writeup of the flaw as well [2].

[1] http://svn.apache.org/viewvc?view=revision&revision=1230065 [2] http://www.halfdog.net/Security/2011/ApacheScoreboardInvalidFreeOnShutdown/

Additional problems were discovered in the httpd fix for CVE-2011-3368 - a reverse proxy bypass flaw - tracked via bug #740045. Upstream mailing list post identifies following request forms, which are not handled correctly:

GET @localhost::8880 HTTP/1.0\r\n\r\n GET qualys:@qqq.qq.qualys.com HTTP/1.0\r\n\r\n

Reference: http://thread.gmane.org/gmane.comp.apache.devel/46440

SUSE reported that upstream patch for CVE-2011-3368 (bug #740045), when applied to httpd versions before 2.2.18, does not completely address the issue, when attacker sends HTTP 0.9 requests::

https://bugzilla.novell.com/showbug.cgi?id=722545#c15 http://thread.gmane.org/gmane.comp.apache.devel/45978 http://thread.gmane.org/gmane.comp.security.oss.general/6102

The fix has been created upstream and committed to trunk:

http://thread.gmane.org/gmane.comp.apache.devel/45978/focus=45979 http://svn.apache.org/viewvc?view=revision&revision=1188745

Upstream also confirmed this additional fix is not required for httpd versions 2.2.18 and later:

http://thread.gmane.org/gmane.comp.apache.devel/45978/focus=45983 http://thread.gmane.org/gmane.comp.apache.devel/45978/focus=45985

Integer overflow in the appregsub function in server/util.c in the Apache HTTP Server 2.0.x through 2.0.64 and 2.2.x through 2.2.21, when the modsetenvif module is enabled, allows local users to gain privileges via a .htaccess file with a crafted SetEnvIf directive, in conjunction with a crafted HTTP request header, leading to a heap-based buffer overflow.

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.

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.

Memory leak in the aprbrigadesplitline function in buckets/aprbrigade.c in the Apache Portable Runtime Utility library (aka APR-util) before 1.3.10, as used in the modreqtimeout module in the Apache HTTP Server and other software, allows remote attackers to cause a denial of service (memory consumption) via unspecified vectors related to the destruction of an APR bucket.

The (1) modcache and (2) moddav modules in the Apache HTTP Server 2.2.x before 2.2.16 allow remote attackers to cause a denial of service (process crash) via a request that lacks a path.

Quoting httpd 2.2 security page: http://httpd.apache.org/security/vulnerabilities22.html#2.2.15

moderate: modproxyajp DoS CVE-2010-0408

modproxyajp would return the wrong status code if it encountered an error causing a backend server to be put into an error state until the retry timeout expired. A remote attacker could send malicious requests to trigger this issue, resulting in a denial of service.

Affects: 2.2.0 - 2.2.14

Upstream commit: http://svn.apache.org/viewvc?view=revision&revision=917876

Quoting httpd 2.2 security page: http://httpd.apache.org/security/vulnerabilities22.html#2.2.15

low: Request header information leak CVE-2010-0434

A bug in the handling of headers in subrequests could lead to a reuse of memory. In a multithreaded MPM this could possibly cause an information leak from other requests being handled by a different thread.

Affects: 2.2.0 - 2.2.14

Upstream bug: https://issues.apache.org/bugzilla/showbug.cgi?id=48359

Upstream commits (2.2.x branch): http://svn.apache.org/viewvc?view=revision&revision=917867 http://svn.apache.org/viewvc?view=revision&revision=918427

Expat is vulnerable to a denial of service, caused by the improper handling of XML data by the big2toUtf8 function within the libexpat library. A remote attacker could exploit this vulnerability using a specially-crafted XML document containing malformed UTF-8 sequences that trigger a buffer over-read to cause the application to crash.

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

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).

A heap buffer underwrite flaw was found in apr-util's aprstrmatchprecompile() function.

This flaw could allow a remote attacker to overwrite arbitrary heap memory.

The upstream fix is here: http://svn.apache.org/viewvc?view=rev&revision=779880

Description of problem:

In an httpd.conf fragment like:

<Directory ...somepath...> AllowOverride ... Options=IncludesNoEXEC </Directory>

that appears to limit what Options can be set in .htaccess to just IncludeNoexec, but in fact Options Includes is also allowed. I assume that this is an upstream bug but I've not checked if any RH patches touch this part of the code.

Version-Release number of selected component (if applicable):

httpd-2.2.3-22.el5

How reproducible:

100%

Steps to Reproduce: 1. Add a <directory> which permits AllowOverride Options=IncludesNoEXEC 2. create a .htaccess in there and use Options Includes 3. access a file using ssi with #exec Actual results:

the #exec is executed

Expected results:

includesnoexec only should be allowed ie no exec or cgi.

Additional info:

In the httpd source (as patched by the srpm etc), in server/core.c at about line 1288 we have the definition of setallowopts() which contains:

... else if (!strcasecmp(w, "Includes")) { opt = OPTINCLUDES; } else if (!strcasecmp(w, "IncludesNOEXEC")) { opt = (OPTINCLUDES | OPTINCNOEXEC); } ...

I think that should probably be:

... else if (!strcasecmp(w, "Includes")) { opt = (OPTINCLUDES | OPTINCNOEXEC); } else if (!strcasecmp(w, "IncludesNOEXEC")) { opt = OPTINCNOEXEC; } ...

since there is (as far as I can see) no harm allowing the user to specify IncludesNoExec if you allow them to use Includes but not the other way round.

Of course my understanding of the logic in setoptions() might well be flawed but it seems that at least one of the bits set in overrideopts must be set in opt to allow it so the change above looks to do what I would expect - though this might not be what others expect it to mean - ie I might well be misunderstanding what AllowOverride ... Options=IncludesNoEXEC should mean.

Peter Valchev discovered a flaw in the way expat handled malformed UTF-8 sequences when processing XML files. Incorrect UTF-8 sequenced could cause expat to fail to properly detect end of input and continue reading behind the end of input buffer. This results in a crash once reading reaches unmapped memory.

Non-public upstream bug report: http://sourceforge.net/tracker/?func=detail&aid=1990430&groupid=10127&atid=110127

Contents of the report leaked via expat-bugs mailing list posts: http://mail.python.org/pipermail/expat-bugs/2009-January/002781.html

Upstream patch: http://expat.cvs.sourceforge.net/viewvc/expat/expat/lib/xmltokimpl.c?r1=1.13&r2=1.15

References: http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=551936 https://bugs.gentoo.org/showbug.cgi?id=280615