Microsoft Exchange Server 2013 CU23/2016 CU18/2016 CU19/2019 CU7/2019 CU8 unknown vulnerability
|CVSS Meta Temp Score|
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|Current Exploit Price (≈)|
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|CTI Interest Score|
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A vulnerability was found in Microsoft Exchange Server 2013 CU23/2016 CU18/2016 CU19/2019 CU7/2019 CU8 (Groupware Software). It has been classified as very critical. This is going to have an impact on confidentiality, and integrity.
The weakness was disclosed 03/02/2021 as confirmed security guidance (Website). The advisory is shared for download at portal.msrc.microsoft.com. This vulnerability is traded as CVE-2021-26855 since 02/08/2021. The exploitability is told to be easy. It is possible to launch the attack remotely. The exploitation doesn't require any form of authentication. Technical details are unknown but a public exploit is available. The current price for an exploit might be approx. USD $0-$5k (estimation calculated on 03/14/2021).
A public exploit has been developed by Jang (testanull) in Python and been published 2 weeks after the advisory. It is declared as functional. The exploit is shared for download at testbnull.medium.com. As 0-day the estimated underground price was around $25k-$100k.
Applying a patch is able to eliminate this problem. A possible mitigation has been published immediately after the disclosure of the vulnerability.
VideoYoutube: Not available anymore
CVSSv3VulDB Meta Base Score: 9.3
VulDB Meta Temp Score: 8.6
VulDB Base Score: 9.1
VulDB Temp Score: 8.4
VulDB Vector: 🔒
VulDB Reliability: 🔍
Vendor Base Score (Microsoft): 9.1
Vendor Vector (Microsoft): 🔒
NVD Base Score: 9.8
NVD Vector: 🔒
VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍
NVD Base Score: 🔒
Author: Jang (testanull)
Programming Language: 🔒
Price Prediction: 🔍
Current Price Estimation: 🔒
Threat IntelligenceThreat: 🔍
Reaction Time: 🔒
0-Day Time: 🔒
Exposure Time: 🔒
Exploit Delay Time: 🔍
Timeline02/08/2021 CVE assigned
03/02/2021 +22 days Advisory disclosed
03/02/2021 +0 days Countermeasure disclosed
03/03/2021 +0 days VulDB entry created
03/11/2021 +7 days Exploit disclosed
03/14/2021 +3 days VulDB last update
CVE: CVE-2021-26855 (🔒)
scip Labs: https://www.scip.ch/en/?labs.20161013
EntryCreated: 03/03/2021 08:22 AM
Updated: 03/14/2021 12:02 PM
Changes: (18) vulnerability_cvss3_nvd_av vulnerability_cvss3_nvd_ac vulnerability_cvss3_nvd_pr vulnerability_cvss3_nvd_ui vulnerability_cvss3_nvd_s vulnerability_cvss3_nvd_c vulnerability_cvss3_nvd_i vulnerability_cvss3_nvd_a vulnerability_cvss2_nvd_av vulnerability_cvss2_nvd_ac vulnerability_cvss2_nvd_au vulnerability_cvss2_nvd_ci vulnerability_cvss2_nvd_ii vulnerability_cvss2_nvd_ai vulnerability_cvss3_meta_basescore vulnerability_cvss3_meta_tempscore vulnerability_cvss2_nvd_basescore vulnerability_cvss3_nvd_basescore
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