GnuTLS up to 2.7.5 X.509 Certificate access control

CVSS Meta Temp Score
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CTI Interest Score
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4.6$0-$5k0.00

Summaryinfo

A vulnerability, which was classified as critical, was found in GnuTLS up to 2.7.5. This affects an unknown function of the component X.509 Certificate Handler. The manipulation results in access control. This vulnerability is cataloged as CVE-2009-5138. There is no exploit available. This vulnerability has a historic impact due to its background and reception. Applying a patch is advised to resolve this issue.

Detailsinfo

A vulnerability, which was classified as critical, was found in GnuTLS up to 2.7.5 (Network Encryption Software). Affected is some unknown functionality of the component X.509 Certificate Handler. The manipulation with an unknown input leads to a access control vulnerability. CWE is classifying the issue as CWE-264. This is going to have an impact on integrity. CVE summarizes:

GnuTLS before 2.7.6, when the GNUTLS_VERIFY_ALLOW_X509_V1_CA_CRT flag is not enabled, treats version 1 X.509 certificates as intermediate CAs, which allows remote attackers to bypass intended restrictions by leveraging a X.509 V1 certificate from a trusted CA to issue new certificates, a different vulnerability than CVE-2014-1959.

The weakness was shared 03/03/2014 by Daniel Kahn Gillmor as Re: gnutls fails to use Verisign CA cert without a Basic Constraint as confirmed posting (Newsgroup). The advisory is shared for download at thread.gmane.org. The vendor cooperated in the coordination of the public release. This vulnerability is traded as CVE-2009-5138 since 02/26/2014. It is possible to launch the attack remotely. The exploitation doesn't require any form of authentication. There are neither technical details nor an exploit publicly available. The current price for an exploit might be approx. USD $0-$5k (estimation calculated on 06/15/2021). The MITRE ATT&CK project declares the attack technique as T1068. This vulnerability has a historic impact due to its background and reception. The reason for this vulnerability is this part of code: 

flags ^= GNUTLS_VERIFY_ALLOW_X509_V1_CA_CRT;

The vulnerability was handled as a non-public zero-day exploit for at least 2245 days. During that time the estimated underground price was around $5k-$25k. The vulnerability scanner Nessus provides a plugin with the ID 72794 (RHEL 5 : gnutls (RHSA-2014:0247)), which helps to determine the existence of the flaw in a target environment. It is assigned to the family Red Hat Local Security Checks. The commercial vulnerability scanner Qualys is able to test this issue with plugin 166830 (SUSE Enterprise Linux Security Update for gnutls (SUSE-SU-2014:0320-1)).

Applying a patch is able to eliminate this problem. The bugfix is ready for download at gitorious.org. The vulnerability will be addressed with the following lines of code:

flags &= ~(GNUTLS_VERIFY_ALLOW_X509_V1_CA_CRT);

The vulnerability is also documented in the databases at X-Force (91544), Tenable (72794), SecurityFocus (BID 65792†), Secunia (SA57254†) and Vulnerability Center (SBV-43745†). The entries VDB-4876 and VDB-59889 are related to this item. VulDB is the best source for vulnerability data and more expert information about this specific topic.

Productinfo

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Name

Version

License

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 5.3
VulDB Meta Temp Score: 4.6

VulDB Base Score: 5.3
VulDB Temp Score: 4.6
VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv2info

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

NVD Base Score: 🔍

Exploitinginfo

Class: Access control
CWE: CWE-264
CAPEC: 🔍
ATT&CK: 🔍

Physical: No
Local: No
Remote: Yes

Availability: 🔍
Status: Unproven

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Nessus ID: 72794
Nessus Name: RHEL 5 : gnutls (RHSA-2014:0247)
Nessus File: 🔍
Nessus Risk: 🔍
Nessus Family: 🔍
Nessus Port: 🔍

OpenVAS ID: 881895
OpenVAS Name: CentOS Update for gnutls CESA-2014:0247 centos5
OpenVAS File: 🔍
OpenVAS Family: 🔍

Qualys ID: 🔍
Qualys Name: 🔍

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Patch
Status: 🔍

0-Day Time: 🔍

Patch: gitorious.org

Timelineinfo

01/09/2008 🔍
02/25/2014 +2239 days 🔍
02/26/2014 +1 days 🔍
03/03/2014 +5 days 🔍
03/04/2014 +1 days 🔍
03/06/2014 +2 days 🔍
03/06/2014 +0 days 🔍
03/10/2014 +4 days 🔍
03/24/2014 +14 days 🔍
03/26/2014 +2 days 🔍
06/15/2021 +2638 days 🔍

Sourcesinfo

Advisory: Re: gnutls fails to use Verisign CA cert without a Basic Constraint
Researcher: Daniel Kahn Gillmor
Status: Confirmed
Confirmation: 🔍
Coordinated: 🔍

CVE: CVE-2009-5138 (🔍)
GCVE (CVE): GCVE-0-2009-5138
GCVE (VulDB): GCVE-100-12504

OVAL: 🔍

X-Force: 91544 - GnuTLS V1 certificates security bypass, Medium Risk
SecurityFocus: 65792 - GnuTLS Certificate Validation Security Bypass Weakness
Secunia: 57254 - SUSE update for gnutls, Moderately Critical
Vulnerability Center: 43745 - GnuTLS <2.7.6 Remote Security Bypass Vulnerability in X.509 V1 Certificate Validation, Medium

See also: 🔍

Entryinfo

Created: 03/10/2014 09:10
Updated: 06/15/2021 09:46
Changes: 03/10/2014 09:10 (88), 05/24/2017 09:17 (5), 06/15/2021 09:46 (3)
Complete: 🔍
Cache ID: 216:376:103

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

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