VDB-121113 · CVE-2018-8311 · BID 104624

Microsoft Lync/Skype for Business input validation

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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7.4$0-$5k0.00

A vulnerability classified as critical has been found in Microsoft Lync and Skype for Business (Unified Communication Software) (version now known). This affects some unknown processing. The manipulation with an unknown input leads to a input validation vulnerability. CWE is classifying the issue as CWE-20. The product receives input or data, but it does not validate or incorrectly validates that the input has the properties that are required to process the data safely and correctly. This is going to have an impact on confidentiality, integrity, and availability.

The weakness was presented 07/10/2018 as confirmed security update guide (Website). The advisory is shared at portal.msrc.microsoft.com. The public release was coordinated in cooperation with Microsoft. This vulnerability is uniquely identified as CVE-2018-8311 since 03/14/2018. It is possible to initiate the attack remotely. No form of authentication is needed for exploitation. It demands that the victim is doing some kind of user interaction. Neither technical details nor an exploit are publicly available. The price for an exploit might be around USD $0-$5k at the moment (estimation calculated on 04/05/2023). The advisory points out:

A remote code execution vulnerability exists when Skype for Business and Microsoft Lync clients fail to properly sanitize specially crafted content. The vulnerability could corrupt memory in a way that could allow an attacker to execute arbitrary code in the context of the current user. An attacker who successfully exploited the vulnerability could gain the same user rights as the current user. If the current user is logged on with administrative user rights, the attacker could take control of an affected system. An attacker could then install programs; view, change, or delete data; or create new accounts with full user rights.

The vulnerability scanner Nessus provides a plugin with the ID 111045 (Security Updates for Microsoft Skype for Business and Microsoft Lync (July 2018)), which helps to determine the existence of the flaw in a target environment. It is assigned to the family Windows : Microsoft Bulletins and running in the context l. The commercial vulnerability scanner Qualys is able to test this issue with plugin 110321 (Microsoft Lync and Skype for Business Security Update for July 2018).

Applying a patch is able to eliminate this problem. A possible mitigation has been published immediately after the disclosure of the vulnerability.

The vulnerability is also documented in the vulnerability database at Tenable (111045). See 121094 for similar entry.

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CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB CVSS-B Score: 🔍
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CVSSv3info

VulDB Meta Base Score: 7.5
VulDB Meta Temp Score: 7.4

VulDB Base Score: 6.3
VulDB Temp Score: 6.0
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 8.8
NVD Vector: 🔍

CVSSv2info

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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔍
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Exploitinginfo

Class: Input validation
CWE: CWE-20
ATT&CK: Unknown

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: 111045
Nessus Name: Security Updates for Microsoft Skype for Business and Microsoft Lync (July 2018)
Nessus File: 🔍
Nessus Risk: 🔍
Nessus Family: 🔍
Nessus Context: 🔍

Qualys ID: 🔍
Qualys Name: 🔍

Threat Intelligenceinfo

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Countermeasuresinfo

Recommended: Patch
Status: 🔍

Reaction Time: 🔍
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Timelineinfo

03/14/2018 🔍
07/10/2018 +117 days 🔍
07/10/2018 +0 days 🔍
07/10/2018 +0 days 🔍
07/10/2018 +0 days 🔍
07/11/2018 +1 days 🔍
07/13/2018 +2 days 🔍
04/05/2023 +1727 days 🔍

Sourcesinfo

Vendor: microsoft.com

Advisory: portal.msrc.microsoft.com
Status: Confirmed
Confirmation: 🔍
Coordinated: 🔍

CVE: CVE-2018-8311 (🔍)
OVAL: 🔍

SecurityTracker: 1041259
SecurityFocus: 104624 - Microsoft Skype for Business and Lync CVE-2018-8311 Remote Code Execution Vulnerability

scip Labs: https://www.scip.ch/en/?labs.20140918
See also: 🔍

Entryinfo

Created: 07/11/2018 10:41
Updated: 04/05/2023 17:42
Changes: 07/11/2018 10:41 (71), 03/01/2020 15:51 (4), 04/05/2023 17:42 (5)
Complete: 🔍

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