VDB-174827 · CVE-2021-26422 · GCVE-0-2021-26422

Microsoft Lync/Skype for Business Server 2013 CU10/2015 CU11/2019 CU5 privilege escalation

CVSS Meta Temp Score CVSS is a standardized scoring system to determine possibilities of attacks. The Temp Score considers temporal factors like disclosure, exploit and countermeasures. The unique Meta Score calculates the average score of different sources to provide a normalized scoring system.	Current Exploit Price (≈) Our analysts are monitoring exploit markets and are in contact with vulnerability brokers. The range indicates the observed or calculated exploit price to be seen on exploit markets. A good indicator to understand the monetary effort required for and the popularity of an attack.	CTI Interest Score Our Cyber Threat Intelligence team is monitoring different web sites, mailing lists, exploit markets and social media networks. The CTI Interest Score identifies the interest of attackers and the security community for this specific vulnerability in real-time. A high score indicates an elevated risk to be targeted for this vulnerability.
6.3	$0-$5k	0.00

Summaryinfo

A vulnerability identified as critical has been detected in Microsoft Lync and Skype for Business Server 2013 CU10/2015 CU11/2019 CU5. This issue affects some unknown processing. The manipulation leads to an unknown weakness. This vulnerability is uniquely identified as CVE-2021-26422. The attack is possible to be carried out remotely. No exploit exists. To fix this issue, it is recommended to deploy a patch.

Detailsinfo

A vulnerability, which was classified as critical, has been found in Microsoft Lync and Skype for Business Server 2013 CU10/2015 CU11/2019 CU5 (Unified Communication Software). Impacted is confidentiality, integrity, and availability.

The weakness was disclosed 05/11/2021 as confirmed security guidance (Website). It is possible to read the advisory at portal.msrc.microsoft.com. The identification of this vulnerability is CVE-2021-26422. The technical details are unknown and an exploit is not publicly available. The pricing for an exploit might be around USD $0-$5k at the moment (estimation calculated on 05/12/2021).

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

Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Productinfo

Type

Unified Communication Software

Vendor

Microsoft

Name

Version

License

commercial

Website

Vendor: https://www.microsoft.com/

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 7.2
VulDB Meta Temp Score: 6.3

VulDB Base Score: 7.2
VulDB Temp Score: 6.3
VulDB Vector: 🔍
VulDB Reliability: 🔍

Vendor Base Score (Microsoft): 7.2
Vendor Vector (Microsoft): 🔍

CVSSv2info

AV	AC	Au	C	I	A
💳	💳	💳	💳	💳	💳
💳	💳	💳	💳	💳	💳
💳	💳	💳	💳	💳	💳

Vector	Complexity	Authentication	Confidentiality	Integrity	Availability
Unlock	Unlock	Unlock	Unlock	Unlock	Unlock
Unlock	Unlock	Unlock	Unlock	Unlock	Unlock
Unlock	Unlock	Unlock	Unlock	Unlock	Unlock

VulDB Base Score: 🔍
VulDB Temp Score: 🔍
VulDB Reliability: 🔍

Exploitinginfo

Class: Privilege escalation
CWE: Unknown
CAPEC: 🔍
ATT&CK: 🔍

Physical: No
Local: No
Remote: Yes

Availability: 🔍
Status: Unproven

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

0-Day	Unlock	Unlock	Unlock	Unlock
Today	Unlock	Unlock	Unlock	Unlock

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Patch
Status: 🔍

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

Timelineinfo

01/29/2021 🔍
05/11/2021 +102 days 🔍
05/11/2021 +0 days 🔍
05/12/2021 +0 days 🔍
05/13/2021 +1 days 🔍

Sourcesinfo

Vendor: microsoft.com

Advisory: portal.msrc.microsoft.com
Status: Confirmed

CVE: CVE-2021-26422 (🔍)
GCVE (CVE): GCVE-0-2021-26422
GCVE (VulDB): GCVE-100-174827
scip Labs: https://www.scip.ch/en/?labs.20140918

Entryinfo

Created: 05/12/2021 02:05
Updated: 05/13/2021 11:24
Changes: 05/12/2021 02:05 (34), 05/12/2021 02:09 (19), 05/13/2021 11:24 (2)
Complete: 🔍
Cache ID: 216::103