Microsoft Exchange Server up to 2019 CU4 deserialization

CVSS Meta Temp Score
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CTI Interest Score
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8.2$0-$5k0.00

Summaryinfo

A vulnerability classified as critical has been found in Microsoft Exchange Server up to 2019 CU4. This vulnerability affects unknown code. This manipulation causes deserialization. This vulnerability is handled as CVE-2020-0688. The attack can be initiated remotely. Additionally, an exploit exists. It is recommended to apply a patch to fix this issue.

Detailsinfo

A vulnerability was found in Microsoft Exchange Server up to 2019 CU4 (Groupware Software). It has been declared as critical. Affected by this vulnerability is some unknown processing. The manipulation with an unknown input leads to a deserialization vulnerability. The CWE definition for the vulnerability is CWE-502. The product deserializes untrusted data without sufficiently verifying that the resulting data will be valid. As an impact it is known to affect confidentiality, integrity, and availability. The summary by CVE is:

A remote code execution vulnerability exists in Microsoft Exchange software when the software fails to properly handle objects in memory, aka 'Microsoft Exchange Memory Corruption Vulnerability'.

The weakness was released 02/11/2020 as confirmed security update guide (Website). It is possible to read the advisory at portal.msrc.microsoft.com. The public release was coordinated with Microsoft. This vulnerability is known as CVE-2020-0688. The attack can be launched remotely. The exploitation doesn't need any form of authentication. Technical details are unknown but a public exploit is available. The advisory points out:

A remote code execution vulnerability exists in Microsoft Exchange software when the software fails to properly handle objects in memory. An attacker who successfully exploited the vulnerability could run arbitrary code in the context of the System user. An attacker could then install programs; view, change, or delete data; or create new accounts.

A public exploit has been developed by Photubias (Tijl Deneut) in Python and been published 3 weeks after the advisory. It is possible to download the exploit at exploit-db.com. It is declared as attacked. We expect the 0-day to have been worth approximately $25k-$100k. The CISA Known Exploited Vulnerabilities Catalog lists this issue since 11/03/2021 with a due date of 05/03/2022:

Apply updates per vendor instructions.

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 Exploit-DB (48153). Entry connected to this vulnerability is available at VDB-149914. Be aware that VulDB is the high quality source for vulnerability data.

Productinfo

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CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 8.3
VulDB Meta Temp Score: 8.2

VulDB Base Score: 7.3
VulDB Temp Score: 7.0
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 8.8
NVD Vector: 🔍

CNA Base Score: 8.8
CNA Vector: 🔍

CVSSv2info

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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔍
VulDB Temp Score: 🔍
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NVD Base Score: 🔍

Exploitinginfo

Class: Deserialization
CWE: CWE-502 / CWE-20
CAPEC: 🔍
ATT&CK: 🔍

Physical: No
Local: No
Remote: Yes

Availability: 🔍
Access: Public
Status: Attacked
Author: Photubias (Tijl Deneut)
Programming Language: 🔍
Download: 🔍

EPSS Score: 🔍
EPSS Percentile: 🔍

KEV Added: 🔍
KEV Due: 🔍
KEV Remediation: 🔍
KEV Ransomware: 🔍
KEV Notice: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Exploit-DB: 🔍

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Patch
Status: 🔍

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

Timelineinfo

11/04/2019 🔍
02/11/2020 +99 days 🔍
02/11/2020 +0 days 🔍
02/11/2020 +0 days 🔍
02/28/2020 +17 days 🔍
02/05/2025 +1804 days 🔍

Sourcesinfo

Vendor: microsoft.com

Advisory: 156592
Status: Confirmed
Coordinated: 🔍

CVE: CVE-2020-0688 (🔍)
GCVE (CVE): GCVE-0-2020-0688
GCVE (VulDB): GCVE-100-149911
scip Labs: https://www.scip.ch/en/?labs.20161013
See also: 🔍

Entryinfo

Created: 02/11/2020 21:13
Updated: 02/05/2025 05:08
Changes: 02/11/2020 21:13 (42), 03/27/2020 08:00 (25), 03/29/2024 16:30 (22), 04/19/2024 17:54 (9), 09/09/2024 22:29 (2), 02/05/2025 05:08 (12)
Complete: 🔍
Committer: misc
Cache ID: 216::103

Be aware that VulDB is the high quality source for vulnerability data.

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