CVEs / CVE-2021-31196
CVE-2021-31196: Microsoft Exchange Server Information Disclosure Vulnerability
- Known exploited in the CISA KEV catalog since 21 Aug 2024
- medium 6.5 CVSS 2.0 (NVD)
- EPSS 54% chance of exploitation in the next 30 days, higher than 99% of CVEs (30 Oct 2026)
- Last changed at its sources
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Summary
Microsoft Exchange Server contains an information disclosure vulnerability that allows for remote code execution.
Description
Microsoft Exchange Server Remote Code Execution Vulnerability
Affected and fixed versions
| Product | Affected | Fixed in |
|---|---|---|
| Microsoft Microsoft Exchange Server 2013 Cumulative Update 23 | from 15.00.0, before 15.00.1497.023 | 15.00.1497.023 |
| Microsoft Microsoft Exchange Server 2016 Cumulative Update 20 | from 15.01.0, before 15.01.2242.012 | 15.01.2242.012 |
| Microsoft Microsoft Exchange Server 2016 Cumulative Update 21 | from 15.01.0, before 15.01.2308.014 | 15.01.2308.014 |
| Microsoft Microsoft Exchange Server 2019 Cumulative Update 10 | from 15.02.0, before 15.02.0922.013 | 15.02.0922.013 |
| Microsoft Microsoft Exchange Server 2019 Cumulative Update 9 | from 15.02.0, before 15.02.0858.015 | 15.02.0858.015 |
Exploitation
| In CISA KEV since | 21 Aug 2024 |
|---|---|
| Due date for US federal agencies | 11 Sep 2024 |
| Used in ransomware campaigns | Unknown |
| Required action | Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable. |
Severity
| CVSS 2.0 | 6.5 mediumAV:N/AC:L/Au:S/C:P/I:P/A:PScored by NVD |
|---|
References
- CVE-2021-31196 on NVD
- CVE-2021-31196 in the CISA KEV catalog
- https://msrc.microsoft.com/update-guide/en-US/advisory/CVE-2021-31196 (cited by CISA)
- https://msrc.microsoft.com/update-guide/vulnerability/CVE-2021-31196 Patch, Vendor Advisory
- https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-31196 Patch, Vendor Advisory
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-31196 US Government Resource
Sources
Exploitation status from the CISA Known Exploited Vulnerabilities catalog. EPSS scores from FIRST. Descriptions, severity and references from the National Vulnerability Database. Open-source package versions from OSV (CC-BY 4.0). Text is shown as each source states it; Stackurity does not edit it. Check the vendor's advisory before acting.
This product uses data from the NVD API but is not endorsed or certified by the NVD.