Linux Kernel up to 4.11-rc7 Keyring signature verification

CVSS Meta Temp Score
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CTI Interest Score
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5.3$0-$5k0.00

Summaryinfo

A vulnerability identified as critical has been detected in Linux Kernel up to 4.11-rc7. Affected by this vulnerability is an unknown functionality of the component Keyring Handler. The manipulation leads to signature verification. This vulnerability is traded as CVE-2016-9604. It is possible to initiate the attack remotely. There is no exploit available. You should upgrade the affected component.

Detailsinfo

A vulnerability was found in Linux Kernel up to 4.11-rc7 (Operating System). It has been rated as critical. This issue affects some unknown functionality of the component Keyring Handler. The manipulation with an unknown input leads to a signature verification vulnerability. Using CWE to declare the problem leads to CWE-347. The product does not verify, or incorrectly verifies, the cryptographic signature for data. Impacted is confidentiality, integrity, and availability. The summary by CVE is:

It was discovered in the Linux kernel before 4.11-rc8 that root can gain direct access to an internal keyring, such as '.dns_resolver' in RHEL-7 or '.builtin_trusted_keys' upstream, by joining it as its session keyring. This allows root to bypass module signature verification by adding a new public key of its own devising to the keyring.

The bug was discovered 04/28/2017. The weakness was shared 07/11/2018 (Website). It is possible to read the advisory at people.canonical.com. The identification of this vulnerability is CVE-2016-9604 since 11/23/2016. The attack may be initiated remotely. A simple authentication is required for exploitation. The technical details are unknown and an exploit is not publicly available.

The vulnerability was handled as a non-public zero-day exploit for at least 84 days. During that time the estimated underground price was around $5k-$25k. The vulnerability scanner Nessus provides a plugin with the ID 101929 (Ubuntu 16.04 LTS : linux-hwe vulnerabilities (USN-3361-1)), which helps to determine the existence of the flaw in a target environment. It is assigned to the family Ubuntu Local Security Checks and running in the context l. The commercial vulnerability scanner Qualys is able to test this issue with plugin 276636 (Fedora Security Update for kernel (FEDORA-2017-17d1c05236)).

Upgrading to version 4.11-rc8 eliminates this vulnerability. A possible mitigation has been published even before and not after the disclosure of the vulnerability.

The vulnerability is also documented in the databases at Tenable (101929) and SecurityFocus (BID 102135†). The entries VDB-96560, VDB-96564 and VDB-97210 are related to this item. Be aware that VulDB is the high quality source for vulnerability data.

Productinfo

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CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 5.4
VulDB Meta Temp Score: 5.3

VulDB Base Score: 7.3
VulDB Temp Score: 7.0
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 4.4
NVD Vector: 🔍

CNA Base Score: 4.4
CNA Vector (Red Hat, Inc.): 🔍

CVSSv2info

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

NVD Base Score: 🔍

Exploitinginfo

Class: Signature verification
CWE: CWE-347 / CWE-345
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: 101929
Nessus Name: Ubuntu 16.04 LTS : linux-hwe vulnerabilities (USN-3361-1)
Nessus File: 🔍
Nessus Risk: 🔍
Nessus Family: 🔍
Nessus Context: 🔍

OpenVAS ID: 867773
OpenVAS Name: Fedora Update for kernel FEDORA-2017-17d1c05236
OpenVAS File: 🔍
OpenVAS Family: 🔍

Qualys ID: 🔍
Qualys Name: 🔍

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔍

Upgrade: Kernel 4.11-rc8
Patch: git.kernel.org

Timelineinfo

11/23/2016 🔍
04/18/2017 +146 days 🔍
04/28/2017 +10 days 🔍
07/21/2017 +84 days 🔍
07/24/2017 +3 days 🔍
07/11/2018 +351 days 🔍
07/11/2018 +0 days 🔍
07/12/2018 +1 days 🔍
04/06/2023 +1729 days 🔍

Sourcesinfo

Vendor: kernel.org

Advisory: USN-3361-1
Status: Not defined
Confirmation: 🔍

CVE: CVE-2016-9604 (🔍)
GCVE (CVE): GCVE-0-2016-9604
GCVE (VulDB): GCVE-100-121319
SecurityFocus: 102135 - Linux Kernel 'security/keys/keyctl.c' Local Security Bypass Vulnerability

See also: 🔍

Entryinfo

Created: 07/12/2018 09:53
Updated: 04/06/2023 16:22
Changes: 07/12/2018 09:53 (78), 03/04/2020 08:52 (4), 04/06/2023 16:07 (5), 04/06/2023 16:15 (12), 04/06/2023 16:22 (1)
Complete: 🔍
Cache ID: 216::103

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