CVE-2021-26427: microsoft exchange_server
CVSS: 9.0v3.1CriticalModified
Published 13-10-2021Last modified 03-08-2024
Vulnerability summary
CVE-2021-26427 is a critical (CVSS 9.0) vulnerability in microsoft exchange_server. EPSS estimates a 0.89% chance of exploitation in the next 30 days, higher than 58.8% of scored vulnerabilities.
CVSS score
9.0/10
010
Critical · v3.1 (CVE.org)EPSS score
0.89%
0%100%
Low · 0.00 pp in 30 daysKEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded
Timeline
- 13-10-2021PublishedVulnerability first disclosed.
- 03-08-2024Last modifiedVulnerability information updated.
Description
Microsoft Exchange Server Remote Code Execution Vulnerability
CVSS metrics
3 scores · 2 sources · 2 versionsCritical 9.0Preferred score · CVE.org (CNA)
CVSS:3.1/AV:A/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H/E:U/RL:O/RC:CSourcesAll 2 agree
- NVDNIST9.0CriticalCVSS:3.1/AV:A/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H
Medium 5.8Preferred score · NVD (NIST)
AV:A/AC:L/Au:N/C:P/I:P/A:PSourcesSingle source
EPSS trend
Probability
0.89%
Chance of exploitation in the next 30 days
Percentile
59%
Versus all other CVEs
30-day change
0.00 pp
From 0.89% on 20-09-2026
20-09-202620-10-2026
EPSS score0.89%
Known exploited
Compare KEV catalogsNot in any of the 3 tracked catalogs.
Public exploits
0 foundNo public exploits indexed.
Weaknesses
CWE · root causeNo weakness data has been published for this record.
Affected systems
Microsoft6 products
- exchange_server2013:cumulative_update_23 | 2016:cumulative_update_21 | 2016:cumulative_update_22 | 2019:cumulative_update_10 | 2019:cumulative_update_11
- microsoft exchange server 2013 cumulative update 23≥ 15.00.0, < 15.00.1497.024
- microsoft exchange server 2016 cumulative update 21≥ 15.01.0, < 15.01.2308.015
- microsoft exchange server 2016 cumulative update 22≥ 15.0.0, < 15.01.2375.012
- microsoft exchange server 2019 cumulative update 10≥ 15.02.0, < 15.02.0922.014
1 vendor · 6 products
References
1 links- portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-26427X Refsource MISCPatchVendor Advisory