libxml2 XML Internal Entity Expansion ENTITY memory corruption

CVSS Meta Temp Score
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CTI Interest Score
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4.8$0-$5k0.00

Summaryinfo

A vulnerability labeled as problematic has been found in libxml2. This issue affects some unknown processing of the component XML Internal Entity Expansion Handler. The manipulation of the argument ENTITY with the input <!ENTITY a "xxx…"]><bomb>&a;&a;&a;...</bomb> as part of XML File results in memory corruption. This vulnerability is identified as CVE-2013-0338. The attack can be executed remotely. Additionally, an exploit exists. It is advisable to implement a patch to correct this issue.

Detailsinfo

A vulnerability was found in libxml2 (Document Processing Software) (the affected version unknown). It has been classified as problematic. Affected is an unknown part of the component XML Internal Entity Expansion Handler. The manipulation of the argument ENTITY with the input value <!ENTITY a "xxx…"]><bomb>&a;&a;&a;...</bomb> leads to a memory corruption vulnerability. CWE is classifying the issue as CWE-119. The product performs operations on a memory buffer, but it can read from or write to a memory location that is outside of the intended boundary of the buffer. This is going to have an impact on availability. CVE summarizes:

libxml2 2.9.0 and earlier allows context-dependent attackers to cause a denial of service (CPU and memory consumption) via an XML file containing an entity declaration with long replacement text and many references to this entity, aka "internal entity expansion" with linear complexity.

The weakness was released 02/19/2013 by Kurt Seifried as CVEs for libxml2 and expat internal and external XML entity expansion as confirmed mailinglist post (oss-sec). The advisory is shared for download at seclists.org. The public release was coordinated with the vendor. This vulnerability is traded as CVE-2013-0338 since 12/06/2012. The exploitability is told to be easy. It is possible to launch the attack remotely. The exploitation doesn't require any form of authentication. Technical details and a public exploit are known.

A public exploit has been developed by Kurt Seifried in XML and been published immediately after the advisory. The exploit is shared for download at seclists.org. It is declared as proof-of-concept. The vulnerability scanner Nessus provides a plugin with the ID 68767 (Oracle Linux 5 / 6 : libxml2 (ELSA-2013-0581)), which helps to determine the existence of the flaw in a target environment. It is assigned to the family Oracle Linux Local Security Checks. The commercial vulnerability scanner Qualys is able to test this issue with plugin 216062 (VMware ESXi 4.0.0 Patch Release ESXi400-201310001 Missing (KB2059496)).

Applying a patch is able to eliminate this problem. The bugfix is ready for download at git.gnome.org. A possible mitigation has been published immediately after the disclosure of the vulnerability.

The vulnerability is also documented in the databases at Tenable (68767), SecurityFocus (BID 48056†), OSVDB (90631†), Secunia (SA52277†) and SecurityTracker (ID 1028212†). Entries connected to this vulnerability are available at VDB-6348, VDB-7759, VDB-7835 and VDB-68676. Once again VulDB remains the best source for vulnerability data.

Productinfo

Type

Name

License

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 5.3
VulDB Meta Temp Score: 4.8

VulDB Base Score: 5.3
VulDB Temp Score: 4.8
VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv2info

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VulDB Base Score: 🔍
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Exploitinginfo

Class: Memory corruption
CWE: CWE-119
CAPEC: 🔍
ATT&CK: 🔍

Physical: No
Local: No
Remote: Yes

Availability: 🔍
Access: Public
Status: Proof-of-Concept
Author: Kurt Seifried
Programming Language: 🔍
Download: 🔍

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Nessus ID: 68767
Nessus Name: Oracle Linux 5 / 6 : libxml2 (ELSA-2013-0581)
Nessus File: 🔍
Nessus Risk: 🔍
Nessus Family: 🔍
Nessus Port: 🔍

OpenVAS ID: 892652
OpenVAS Name: Debian Security Advisory DSA 2652-1 (libxml2 - external entity expansion
OpenVAS File: 🔍
OpenVAS Family: 🔍

Qualys ID: 🔍
Qualys Name: 🔍

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Patch
Status: 🔍

Reaction Time: 🔍
0-Day Time: 🔍
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Exploit Delay Time: 🔍

Patch: git.gnome.org

Timelineinfo

05/31/2011 🔍
12/06/2012 +555 days 🔍
02/19/2013 +75 days 🔍
02/19/2013 +0 days 🔍
02/19/2013 +0 days 🔍
02/26/2013 +7 days 🔍
02/28/2013 +2 days 🔍
04/25/2013 +56 days 🔍
07/12/2013 +78 days 🔍
05/05/2021 +2854 days 🔍

Sourcesinfo

Advisory: CVEs for libxml2 and expat internal and external XML entity expansion
Researcher: Kurt Seifried
Status: Confirmed
Confirmation: 🔍
Coordinated: 🔍

CVE: CVE-2013-0338 (🔍)
GCVE (CVE): GCVE-0-2013-0338
GCVE (VulDB): GCVE-100-7836

OVAL: 🔍

SecurityFocus: 48056 - libxml2 Invalid XPath Multiple Memory Corruption Vulnerabilities
Secunia: 52277 - Libxml2 Entity Expansion Denial of Service Vulnerability, Less Critical
OSVDB: 90631
SecurityTracker: 1028212 - Libxml2 Entity Expansion May Let Remote Users Deny Service

scip Labs: https://www.scip.ch/en/?labs.20161013
See also: 🔍

Entryinfo

Created: 02/28/2013 10:40
Updated: 05/05/2021 15:21
Changes: 02/28/2013 10:40 (81), 04/13/2017 12:26 (5), 05/05/2021 15:14 (8), 05/05/2021 15:21 (1)
Complete: 🔍
Cache ID: 216::103

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