Home page logo
/

oss-sec logo oss-sec mailing list archives

Re: CVE for Ruby Entity expansion DoS vulnerability in REXML (XML bomb)
From: "U.Nakamura" <usa () garbagecollect jp>
Date: Mon, 11 Mar 2013 16:46:19 +0900

Hello,

Thank you for your information.
I've just added the CVE identifier to our site now.

Sorry for late reply.


In message "CVE for Ruby Entity expansion DoS vulnerability in REXML (XML bomb)"
    on Mar.07,2013 03:25:13, <kseifried () redhat com> wrote:
-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1

http://www.ruby-lang.org/en/news/2013/02/22/rexml-dos-2013-02-22/

=====

Unrestricted entity expansion can lead to a DoS vulnerability in
REXML. (The CVE identifier will be assigned later.) We strongly
recommend to upgrade ruby.
Details

When reading text nodes from an XML document, the REXML parser can be
coerced in to allocating extremely large string objects which can
consume all of the memory on a machine, causing a denial of service.

Impacted code will look something like this:

document = REXML::Document.new some_xml_doc
document.root.text

When the `text` method is called, entities will be expanded. An
attacker can send a relatively small XML document that, when the
entities are resolved, will consume extreme amounts of memory on the
target system.

Note that this attack is similar to, but different from the Billion
Laughs attack. This is also related to CVE-2013-1664 of Python.

All users running an affected release should either upgrade or use one
of the work arounds immediately.

=====

Please use CVE-2013-1821 for this issue. I apologize in advance if a
CVE was requested through other channels but we need a CVE for this
ASAP. Also for future reference you can get CVEs via

http://people.redhat.com/kseifrie/CVE-OpenSource-Request-HOWTO.html

- -- 
Kurt Seifried Red Hat Security Response Team (SRT)
PGP: 0x5E267993 A90B F995 7350 148F 66BF 7554 160D 4553 5E26 7993

-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.4.13 (GNU/Linux)
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=7jHF
-----END PGP SIGNATURE-----


Regards,
-- 
U.Nakamura <usa () garbagecollect jp>

Attachment: _bin
Description:


  By Date           By Thread  

Current thread:
[ Nmap | Sec Tools | Mailing Lists | Site News | About/Contact | Advertising | Privacy ]
AlienVault