libxml2 up to 2.9.3 parser.c xmlStringLenDecodeEntities input validation

CVSS Meta Temp Score
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CTI Interest Score
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8.3$0-$5k0.00

Summaryinfo

A vulnerability, which was classified as critical, has been found in libxml2 up to 2.9.3. Affected is the function xmlStringLenDecodeEntities of the file parser.c. This manipulation causes input validation. This vulnerability appears as CVE-2016-4449. The attack may be initiated remotely. There is no available exploit. It is advisable to upgrade the affected component.

Detailsinfo

A vulnerability classified as very critical was found in libxml2 up to 2.9.3 (Document Processing Software). Affected by this vulnerability is the function xmlStringLenDecodeEntities of the file parser.c. The manipulation with an unknown input leads to a input validation vulnerability. The CWE definition for the vulnerability is CWE-20. The product receives input or data, but it does not validate or incorrectly validates that the input has the properties that are required to process the data safely and correctly. As an impact it is known to affect confidentiality, integrity, and availability. The summary by CVE is:

XML external entity (XXE) vulnerability in the xmlStringLenDecodeEntities function in parser.c in libxml2 before 2.9.4, when not in validating mode, allows context-dependent attackers to read arbitrary files or cause a denial of service (resource consumption) via unspecified vectors.

The weakness was presented 06/09/2016 by Daniel Veillard (Website). It is possible to read the advisory at debian.org. This vulnerability is known as CVE-2016-4449 since 05/02/2016. The attack can be launched remotely. The exploitation doesn't need any form of authentication. Technical details of the vulnerability are known, but there is no available exploit. The pricing for an exploit might be around USD $0-$5k at the moment (estimation calculated on 08/23/2022).

The vulnerability scanner Nessus provides a plugin with the ID 91447 (Debian DSA-3593-1 : libxml2 - security update), which helps to determine the existence of the flaw in a target environment. It is assigned to the family Debian Local Security Checks and running in the context l. The commercial vulnerability scanner Qualys is able to test this issue with plugin 43650 (Juniper Junos Multiple vulnerabilities in libxml2 (JSA10916)).

Upgrading to version 2.9.4 eliminates this vulnerability. A possible mitigation has been published before and not just after the disclosure of the vulnerability.

The vulnerability is also documented in the databases at Tenable (91447) and SecurityFocus (BID 90865†). See VDB-79335, VDB-79336, VDB-79337 and VDB-79338 for similar entries. Be aware that VulDB is the high quality source for vulnerability data.

Productinfo

Type

Name

Version

License

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 8.5
VulDB Meta Temp Score: 8.3

VulDB Base Score: 9.8
VulDB Temp Score: 9.4
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 7.1
NVD Vector: 🔍

CVSSv2info

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VulDB Base Score: 🔍
VulDB Temp Score: 🔍
VulDB Reliability: 🔍

NVD Base Score: 🔍

Exploitinginfo

Class: Input validation
CWE: CWE-20
CAPEC: 🔍
ATT&CK: 🔍

Physical: Partially
Local: Yes
Remote: Yes

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Nessus ID: 91447
Nessus Name: Debian DSA-3593-1 : libxml2 - security update
Nessus File: 🔍
Nessus Risk: 🔍
Nessus Family: 🔍
Nessus Context: 🔍

OpenVAS ID: 14611
OpenVAS Name: Amazon Linux Local Check: alas-2016-719
OpenVAS File: 🔍
OpenVAS Family: 🔍

Qualys ID: 🔍
Qualys Name: 🔍

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔍

Upgrade: libxml2 2.9.4
Patch: git.gnome.org

Timelineinfo

05/02/2016 🔍
05/23/2016 +21 days 🔍
06/02/2016 +10 days 🔍
06/03/2016 +1 days 🔍
06/09/2016 +6 days 🔍
06/09/2016 +0 days 🔍
06/10/2016 +1 days 🔍
08/23/2022 +2265 days 🔍

Sourcesinfo

Advisory: RHSA-2016:1292
Researcher: Daniel Veillard
Status: Confirmed
Confirmation: 🔍

CVE: CVE-2016-4449 (🔍)
GCVE (CVE): GCVE-0-2016-4449
GCVE (VulDB): GCVE-100-87823

OVAL: 🔍

SecurityFocus: 90865 - Libxml2 'xmlLoadEntityContent()' Function CVE-2016-4449 Security Bypass Vulnerability
SecurityTracker: 1036348

See also: 🔍

Entryinfo

Created: 06/10/2016 09:39
Updated: 08/23/2022 10:56
Changes: 06/10/2016 09:39 (61), 01/14/2019 08:04 (20), 08/23/2022 10:56 (5)
Complete: 🔍
Cache ID: 216::103

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