GnuTLS up to 3.4.14/3.5.3 OCSP Response Length lib/x509/ocsp.c gnutls_ocsp_resp_check_crt access control

CVSS Meta Temp Score
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CTI Interest Score
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7.3$0-$5k0.00

A vulnerability was found in GnuTLS up to 3.4.14/3.5.3 (Network Encryption Software). It has been declared as critical. Affected by this vulnerability is the function gnutls_ocsp_resp_check_crt in the library lib/x509/ocsp.c of the component OCSP Response Length Handler. The manipulation with an unknown input leads to a access control vulnerability. The CWE definition for the vulnerability is CWE-264. As an impact it is known to affect confidentiality, integrity, and availability. The summary by CVE is:

The gnutls_ocsp_resp_check_crt function in lib/x509/ocsp.c in GnuTLS before 3.4.15 and 3.5.x before 3.5.4 does not verify the serial length of an OCSP response, which might allow remote attackers to bypass an intended certificate validation mechanism via vectors involving trailing bytes left by gnutls_malloc.

The weakness was released 09/27/2016 (Website). The advisory is shared at gitlab.com. This vulnerability is known as CVE-2016-7444 since 09/09/2016. The exploitation appears to be easy. The attack can be launched remotely. The exploitation doesn't need any form of authentication. Technical details are known, but no exploit is available. MITRE ATT&CK project uses the attack technique T1068 for this issue.

The vulnerability scanner Nessus provides a plugin with the ID 94844 (Fedora 25 : mingw-gnutls (2016-a1e5b2331a)), which helps to determine the existence of the flaw in a target environment. It is assigned to the family Fedora Local Security Checks and running in the context l. The commercial vulnerability scanner Qualys is able to test this issue with plugin 157522 (Oracle Enterprise Linux Security Update for gnutls (ELSA-2017-2292)).

Upgrading to version 3.4.15 or 3.5.4 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 vulnerability database at Tenable (94844).

Productinfo

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CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB CVSS-B Score: 🔍
VulDB CVSS-BT Score: 🔍
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CVSSv3info

VulDB Meta Base Score: 7.5
VulDB Meta Temp Score: 7.3

VulDB Base Score: 7.5
VulDB Temp Score: 7.2
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 7.5
NVD Vector: 🔍

CVSSv2info

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VulDB Base Score: 🔍
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VulDB Reliability: 🔍

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Exploitinginfo

Class: Access control
CWE: CWE-264
ATT&CK: T1068

Local: No
Remote: Yes

Availability: 🔍
Status: Not defined

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EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Nessus ID: 94844
Nessus Name: Fedora 25 : mingw-gnutls (2016-a1e5b2331a)
Nessus File: 🔍
Nessus Risk: 🔍
Nessus Family: 🔍
Nessus Context: 🔍

OpenVAS ID: 871165
OpenVAS Name: RedHat Update for gnutls RHSA-2017:2292-01
OpenVAS File: 🔍
OpenVAS Family: 🔍

Qualys ID: 🔍
Qualys Name: 🔍

Threat Intelligenceinfo

Interest: 🔍
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Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔍

Upgrade: GnuTLS 3.4.15/3.5.4
Patch: gitlab.com

Timelineinfo

09/02/2016 🔍
09/09/2016 +7 days 🔍
09/14/2016 +5 days 🔍
09/27/2016 +13 days 🔍
09/27/2016 +0 days 🔍
09/28/2016 +1 days 🔍
11/15/2016 +48 days 🔍
09/21/2022 +2136 days 🔍

Sourcesinfo

Advisory: RHSA-2017:2292
Status: Not defined
Confirmation: 🔍

CVE: CVE-2016-7444 (🔍)
SecurityFocus: 92893 - GnuTLS GNUTLS-SA-2016-3 Certificate Validation Security Bypass Vulnerability

Entryinfo

Created: 09/28/2016 09:12
Updated: 09/21/2022 14:36
Changes: 09/28/2016 09:12 (66), 04/27/2019 09:27 (13), 09/21/2022 14:36 (5)
Complete: 🔍

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