Varnish before 3.0.5 allows remote attackers to cause a denial of service (child-process crash and temporary caching outage) via a GET request with trailing whitespace characters and no URI.

The remote host is affected by the vulnerability described in GLSA-201412-30 (Varnish: Multiple vulnerabilities)

    Multiple vulnerabilities have been discovered in Varnish. Please review       the CVE identifiers referenced below for details.
  Impact :

    A remote attacker could cause a Denial of Service condition via a       specially crafted GET request. Furthermore a local attacker could obtain       sensitive information through insecure permissions on logfiles.
  Workaround :

    There is no known workaround at this time.

This update fixes the following security issue with varnish :

  - bnc#848451, CVE-2013-4484: fixed denial of service flaw     in certain GET requests when using certain     configurations in Varnish Cache handling

  - bnc#839358: Deactivate libpcre JIT

This update fixes the following security issue with varnish :

  - bnc#848451, CVE-2013-4484: fixed denial of service flaw     in certain GET requests when using certain     configurations in Varnish Cache handling

New upstream release 3.0.5. List of changes available at https://www.varnish-cache.org/releases/varnish-cache-3.0.5

  - Changed default mask for varnish log dir to 700, closing     #915413

    - Added a patch for CVE-2013-4484 from upstream, closing       #1025128

Note that Tenable Network Security has extracted the preceding description block directly from the Fedora security advisory. Tenable has attempted to automatically clean and format it as much as possible without introducing additional issues.

Updated varnish packages fix security vulnerabilities :

Varnish before 3.0.5 allows remote attackers to cause a denial of service (child-process crash and temporary caching outage) via a GET request with trailing whitespace characters and no URI (CVE-2013-4484).

Also, the services have been converted from SysV init scripts to systemd-native services, which should allow for more consistent behavior.

Varnish before 3.0.5 allows remote attackers to cause a denial of service (child-process crash and temporary caching outage) via a GET request with trailing whitespace characters and no URI.

varnish 3.0.3 uses world-readable permissions for the /var/log/varnish/ directory and the log files in the directory, which allows local users to obtain sensitive information by reading the files. NOTE: some of these details are obtained from third party information.

Varnish Cache Project reports :

If Varnish receives a certain illegal request, and the subroutine 'vcl_error{}' restarts the request, the varnishd worker process will crash with an assert.

The varnishd management process will restart the worker process, but there will be a brief interruption of service and the cache will be emptied, causing more traffic to go to the backend.

We are releasing this advisory because restarting from vcl_error{} is both fairly common and documented.

This is purely a denial of service vulnerability, there is no risk of privilege escalation.

Workaround

Insert this at the top of your VCL file :

sub vcl_error { if (obj.status == 400 || obj.status == 413) { return(deliver); } }

Or add this test at the top of your existing vcl_error{}.

A denial of service vulnerability was reported in varnish, a state of the art, high-performance web accelerator. With some configurations of varnish a remote attacker could mount a denial of service (child-process crash and temporary caching outage) via a GET request with trailing whitespace characters and no URI.

ID	Name	Product	Family	Severity
80040	GLSA-201412-30 : Varnish: Multiple vulnerabilities	Nessus	Gentoo Local Security Checks	medium
75203	openSUSE Security Update : varnish (openSUSE-SU-2013:1683-1)	Nessus	SuSE Local Security Checks	medium
75202	openSUSE Security Update : varnish (openSUSE-SU-2013:1679-1)	Nessus	SuSE Local Security Checks	medium
73871	Fedora 19 : varnish-3.0.5-1.fc19 (2013-24023)	Nessus	Fedora Local Security Checks	medium
73870	Fedora 20 : varnish-3.0.5-1.fc20 (2013-24018)	Nessus	Fedora Local Security Checks	medium
72551	Mandriva Linux Security Advisory : varnish (MDVSA-2014:036)	Nessus	Mandriva Local Security Checks	medium
72294	Amazon Linux AMI : varnish (ALAS-2014-276)	Nessus	Amazon Linux Local Security Checks	medium
72128	FreeBSD : varnish -- DoS vulnerability in Varnish HTTP cache (d9dbe6e8-84da-11e3-98bd-080027f2d077)	Nessus	FreeBSD Local Security Checks	medium
71277	Debian DSA-2814-1 : varnish - denial of service	Nessus	Debian Local Security Checks	medium

Detections

Analytics

CVE-2013-4484

high

Tenable Plugins

medium

medium

medium

medium

medium

medium

medium

medium

medium