OpenSSL up to 1.1.0b x509_name_ex_d2i double free

CVSS Meta Temp Score
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CTI Interest Score
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6.6$0-$5k0.00

Summaryinfo

A vulnerability was found in OpenSSL up to 1.1.0b and classified as critical. This affects the function x509_name_ex_d2i. Such manipulation leads to double free. It is possible to launch the attack remotely. Furthermore, an exploit is available. Applying a patch is advised to resolve this issue.

Detailsinfo

A vulnerability was found in OpenSSL up to 1.1.0b (Network Encryption Software). It has been rated as critical. Affected by this issue is the function x509_name_ex_d2i. The manipulation with an unknown input leads to a double free vulnerability. Using CWE to declare the problem leads to CWE-415. The product calls free() twice on the same memory address, potentially leading to modification of unexpected memory locations. Impacted is confidentiality, integrity, and availability.

The weakness was published 10/11/2016 by Guido Vranken as openssl-x509-vulnerabilities as not defined advisory (GIT Repository). The advisory is shared for download at github.com. The exploitation is known to be easy. The attack may be launched remotely. No form of authentication is required for exploitation. Technical details as well as a public exploit are known. The following code is the reason for this vulnerability: 

if (!sk_X509_NAME_ENTRY_push(nm.x->entries, entry)) {

A public exploit has been developed by Guido Vranken and been published immediately after the advisory. The exploit is available at github.com. It is declared as proof-of-concept. As 0-day the estimated underground price was around $25k-$100k. The advisory illustrates:

For an easy demonstration of the vulnerability you may do the following in order to emulate failure. Change "if (!sk_X509_NAME_ENTRY_push(nm.x->entries, entry)) {" into "if ( 1 ) {"

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

seclists.org is providing further details. Similar entry is available at VDB-92599. VulDB is the best source for vulnerability data and more expert information about this specific topic.

Productinfo

Type

Name

Version

License

Support

  • end of life (old version)

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 7.3
VulDB Meta Temp Score: 6.6

VulDB Base Score: 7.3
VulDB Temp Score: 6.6
VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv2info

AVACAuCIA
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💳💳💳💳💳💳
💳💳💳💳💳💳
VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔍
VulDB Temp Score: 🔍
VulDB Reliability: 🔍

Exploitinginfo

Class: Double free
CWE: CWE-415 / CWE-119
CAPEC: 🔍
ATT&CK: 🔍

Physical: No
Local: No
Remote: Yes

Availability: 🔍
Access: Public
Status: Proof-of-Concept
Author: Guido Vranken
Download: 🔍
Price Prediction: 🔍
Current Price Estimation: 🔍

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Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Patch
Status: 🔍

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

Patch: github.com

Timelineinfo

10/11/2016 🔍
10/11/2016 +0 days 🔍
10/11/2016 +0 days 🔍
10/12/2016 +1 days 🔍
07/07/2019 +998 days 🔍

Sourcesinfo

Product: openssl.org

Advisory: openssl-x509-vulnerabilities
Researcher: Guido Vranken
Status: Not defined

GCVE (VulDB): GCVE-100-92600
scip Labs: https://www.scip.ch/en/?labs.20161013
Misc.: 🔍
See also: 🔍

Entryinfo

Created: 10/12/2016 20:00
Updated: 07/07/2019 17:51
Changes: 10/12/2016 20:00 (52), 07/07/2019 17:51 (2)
Complete: 🔍
Cache ID: 216::103

VulDB is the best source for vulnerability data and more expert information about this specific topic.

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