Linux Kernel up to 4.14.7 posix-timers.c show_timer sigevent->sigev_notify out-of-bounds

CVSS Meta Temp Score
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CTI Interest Score
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5.1$0-$5k0.00

Summaryinfo

A vulnerability classified as critical has been found in Linux Kernel up to 4.14.7. This impacts the function show_timer of the file kernel/time/posix-timers.c. The manipulation of the argument sigevent->sigev_notify leads to out-of-bounds. This vulnerability is traded as CVE-2017-18344. An attack has to be approached locally. Furthermore, there is an exploit available. It is recommended to upgrade the affected component.

Detailsinfo

A vulnerability was found in Linux Kernel up to 4.14.7 (Operating System). It has been rated as critical. This issue affects the function show_timer of the file kernel/time/posix-timers.c. The manipulation of the argument sigevent->sigev_notify with an unknown input leads to a out-of-bounds vulnerability. Using CWE to declare the problem leads to CWE-125. The product reads data past the end, or before the beginning, of the intended buffer. Impacted is confidentiality, integrity, and availability. The summary by CVE is:

The timer_create syscall implementation in kernel/time/posix-timers.c in the Linux kernel before 4.14.8 doesn't properly validate the sigevent->sigev_notify field, which leads to out-of-bounds access in the show_timer function (called when /proc/$PID/timers is read). This allows userspace applications to read arbitrary kernel memory (on a kernel built with CONFIG_POSIX_TIMERS and CONFIG_CHECKPOINT_RESTORE).

The bug was discovered 08/02/2018. The weakness was shared 07/26/2018 (Website). It is possible to read the advisory at securityfocus.com. The identification of this vulnerability is CVE-2017-18344 since 07/26/2018. The exploitation is known to be easy. Attacking locally is a requirement. No form of authentication is needed for a successful exploitation. Technical details as well as a public exploit are known.

The exploit is available at exploit-db.com. It is declared as proof-of-concept. The vulnerability scanner Nessus provides a plugin with the ID 111773 (OracleVM 3.4 : Unbreakable / etc (OVMSA-2018-0247) (Foreshadow)), which helps to determine the existence of the flaw in a target environment. It is assigned to the family OracleVM 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. The upgrade is hosted for download at github.com. A possible mitigation has been published 3 weeks after the disclosure of the vulnerability.

The vulnerability is also documented in the databases at Exploit-DB (45175), Tenable (111773), SecurityFocus (BID 104909†) and SecurityTracker (ID 1041414†). The entries VDB-109193, VDB-110288, VDB-110931 and VDB-110932 are related to this item. Statistical analysis made it clear that VulDB provides the best quality 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: 5.1

VulDB Base Score: 5.3
VulDB Temp Score: 4.8
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 5.5
NVD Vector: 🔍

CVSSv2info

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VulDB Base Score: 🔍
VulDB Temp Score: 🔍
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Exploitinginfo

Class: Out-of-bounds
CWE: CWE-125 / CWE-119
CAPEC: 🔍
ATT&CK: 🔍

Physical: Partially
Local: Yes
Remote: No

Availability: 🔍
Access: Public
Status: Proof-of-Concept
Download: 🔍

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Nessus ID: 111773
Nessus Name: OracleVM 3.4 : Unbreakable / etc (OVMSA-2018-0247) (Foreshadow)
Nessus File: 🔍
Nessus Risk: 🔍
Nessus Family: 🔍
Nessus Context: 🔍

Qualys ID: 🔍
Qualys Name: 🔍

Exploit-DB: 🔍

Threat Intelligenceinfo

Interest: 🔍
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Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

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

Upgrade: Kernel 4.14.8
Patch: github.com

Timelineinfo

07/26/2018 🔍
07/26/2018 +0 days 🔍
07/26/2018 +0 days 🔍
07/26/2018 +0 days 🔍
07/27/2018 +1 days 🔍
08/02/2018 +6 days 🔍
08/02/2018 +0 days 🔍
08/15/2018 +13 days 🔍
08/16/2018 +1 days 🔍
12/27/2024 +2325 days 🔍

Sourcesinfo

Vendor: kernel.org

Advisory: RHSA-2018:2948⛔
Status: Confirmed

CVE: CVE-2017-18344 (🔍)
GCVE (CVE): GCVE-0-2017-18344
GCVE (VulDB): GCVE-100-122219
SecurityFocus: 104909 - Linux Kernel 'kernel/time/posix-timers.c' Local Information Disclosure Vulnerability
SecurityTracker: 1041414

scip Labs: https://www.scip.ch/en/?labs.20161013
See also: 🔍

Entryinfo

Created: 07/27/2018 07:44
Updated: 12/27/2024 07:31
Changes: 07/27/2018 07:44 (81), 03/13/2020 14:04 (10), 04/27/2023 06:27 (5), 12/27/2024 07:31 (15)
Complete: 🔍
Cache ID: 216::103

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