Linux Kernel up to 4.14.7 HMAC crypto/hmac.c System Calls memory corruption

CVSS Meta Temp Score
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CTI Interest Score
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7.6$0-$5k0.00

Summaryinfo

A vulnerability labeled as critical has been found in Linux Kernel up to 4.14.7. This affects an unknown function of the file crypto/hmac.c of the component HMAC. Executing a manipulation as part of System Calls can lead to memory corruption. This vulnerability is tracked as CVE-2017-17806. The attack is restricted to local execution. No exploit exists. It is advisable to implement a patch to correct this issue.

Detailsinfo

A vulnerability was found in Linux Kernel up to 4.14.7 (Operating System). It has been declared as critical. This vulnerability affects an unknown part of the file crypto/hmac.c of the component HMAC. The manipulation as part of a System Calls leads to a memory corruption vulnerability. The CWE definition for the vulnerability is CWE-119. The product performs operations on a memory buffer, but it can read from or write to a memory location that is outside of the intended boundary of the buffer. As an impact it is known to affect confidentiality, integrity, and availability. CVE summarizes:

The HMAC implementation (crypto/hmac.c) in the Linux kernel before 4.14.8 does not validate that the underlying cryptographic hash algorithm is unkeyed, allowing a local attacker able to use the AF_ALG-based hash interface (CONFIG_CRYPTO_USER_API_HASH) and the SHA-3 hash algorithm (CONFIG_CRYPTO_SHA3) to cause a kernel stack buffer overflow by executing a crafted sequence of system calls that encounter a missing SHA-3 initialization.

The bug was discovered 11/29/2017. The weakness was disclosed 12/20/2017 as confirmed git commit (GIT Repository). The advisory is shared for download at git.kernel.org. This vulnerability was named CVE-2017-17806 since 12/20/2017. The attack needs to be approached locally. A single authentication is necessary for exploitation. There are known technical details, but no exploit is available.

The vulnerability was handled as a non-public zero-day exploit for at least 21 days. During that time the estimated underground price was around $5k-$25k. The vulnerability scanner Nessus provides a plugin with the ID 105433 (Debian DSA-4073-1 : linux - 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 237034 (Red Hat Update for kernel-alt (RHSA-2018:2948)).

Upgrading to version 4.14.8 eliminates this vulnerability. Applying a patch is able to eliminate this problem. The bugfix is ready for download at git.kernel.org. The best possible mitigation is suggested to be patching the affected component. A possible mitigation has been published 3 days after the disclosure of the vulnerability.

The vulnerability is also documented in the databases at Tenable (105433) and SecurityFocus (BID 102293†). The entries VDB-109193, VDB-110288, VDB-110931 and VDB-110933 are pretty similar. Once again VulDB remains the best source for vulnerability data.

Productinfo

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CVSSv4info

VulDB Vector: 🔍
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CVSSv3info

VulDB Meta Base Score: 7.8
VulDB Meta Temp Score: 7.6

VulDB Base Score: 7.8
VulDB Temp Score: 7.5
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 7.8
NVD Vector: 🔍

CVSSv2info

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VulDB Base Score: 🔍
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Exploitinginfo

Class: Memory corruption
CWE: CWE-119
CAPEC: 🔍
ATT&CK: 🔍

Physical: Partially
Local: Yes
Remote: No

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Nessus ID: 105433
Nessus Name: Debian DSA-4073-1 : linux - security update
Nessus File: 🔍
Nessus Risk: 🔍
Nessus Family: 🔍
Nessus Context: 🔍

OpenVAS ID: 61643
OpenVAS Name: SuSE Update for Linux Kernel openSUSE-SU-2018:0022-1 (Linux Kernel)
OpenVAS File: 🔍
OpenVAS Family: 🔍

Qualys ID: 🔍
Qualys Name: 🔍

Threat Intelligenceinfo

Interest: 🔍
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Countermeasuresinfo

Recommended: Patch
Status: 🔍

Reaction Time: 🔍
0-Day Time: 🔍
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Upgrade: Kernel 4.14.8
Patch: git.kernel.org

Timelineinfo

11/29/2017 🔍
12/20/2017 +21 days 🔍
12/20/2017 +0 days 🔍
12/20/2017 +0 days 🔍
12/20/2017 +0 days 🔍
12/21/2017 +1 days 🔍
12/23/2017 +2 days 🔍
12/26/2017 +3 days 🔍
01/18/2023 +1849 days 🔍

Sourcesinfo

Vendor: kernel.org

Advisory: RHSA-2018:2948
Researcher: syzbot.
Status: Confirmed
Confirmation: 🔍

CVE: CVE-2017-17806 (🔍)
GCVE (CVE): GCVE-0-2017-17806
GCVE (VulDB): GCVE-100-110932

OVAL: 🔍

SecurityFocus: 102293 - Linux Kernel CVE-2017-17806 Stack Based Buffer Overflow Vulnerability

See also: 🔍

Entryinfo

Created: 12/21/2017 08:45
Updated: 01/18/2023 14:19
Changes: 12/21/2017 08:45 (84), 12/17/2019 08:28 (5), 01/27/2021 16:55 (2), 01/18/2023 14:19 (3)
Complete: 🔍
Cache ID: 216:215:103

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