VDB
CVE-2021-26857
CVE-2021-26857
PUBLISHED
CVSS 7.8 HIGH
Microsoft Exchange Server Remote Code Execution Vulnerability
Reported by microsoft · Published March 2, 2021
Microsoft Exchange Server Remote Code Execution Vulnerability
Fixed versions
Upgrade to a fixed version or later. Language registries are listed first, then Linux distributions, then vendor products.
| Package | Ecosystem | Fixed in |
|---|---|---|
| Microsoft Exchange Server 2013 Service Pack 1 | Microsoft | 15.00.0847.064 |
| Microsoft Exchange Server 2016 Cumulative Update 17 | Microsoft | 15.01.2044.013 |
| Microsoft Exchange Server 2013 Cumulative Update 21 | Microsoft | 15.00.1395.012 |
| Microsoft Exchange Server 2019 Cumulative Update 4 | Microsoft | 15.02.0659.012 |
| Microsoft Exchange Server 2019 Cumulative Update 6 | Microsoft | 15.02.0529.013 |
| Microsoft Exchange Server 2019 Cumulative Update 7 | Microsoft | 15.02.0721.013 |
| Microsoft Exchange Server 2019 Cumulative Update 2 | Microsoft | 15.02.0397.011 |
| Microsoft Exchange Server 2019 | Microsoft | 15.02.0221.018 |
| Microsoft Exchange Server 2016 Cumulative Update 16 | Microsoft | 15.01.1979.008 |
| Microsoft Exchange Server 2019 Cumulative Update 8 | Microsoft | 15.02.0792.010 |
| Microsoft Exchange Server 2016 Cumulative Update 8 | Microsoft | 15.01.1415.010 |
| Microsoft Exchange Server 2016 Cumulative Update 9 | Microsoft | 15.01.1466.016 |
3 more packages have a fixed version. See every fix in Lookup.
Risk scores
CVSS 3.1
7.8
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H/E:F/RL:O/RC:C
Affected products
| Vendor | Product | Versions |
|---|---|---|
| Microsoft | Microsoft Exchange Server 2010 Service Pack 3 | 14.0.0.0 |
| Microsoft | Microsoft Exchange Server 2013 Cumulative Update 21 | 15.00.0 |
| Microsoft | Microsoft Exchange Server 2013 Cumulative Update 22 | 15.00.0 |
| Microsoft | Microsoft Exchange Server 2013 Cumulative Update 23 | 15.00.0 |
| Microsoft | Microsoft Exchange Server 2013 Service Pack 1 | 15.00.0 |
| Microsoft | Microsoft Exchange Server 2016 Cumulative Update 10 | 15.01.0 |
| Microsoft | Microsoft Exchange Server 2016 Cumulative Update 11 | 15.01.0 |
| Microsoft | Microsoft Exchange Server 2016 Cumulative Update 12 | 15.01.0 |
| Microsoft | Microsoft Exchange Server 2016 Cumulative Update 13 | 15.01.0 |
| Microsoft | Microsoft Exchange Server 2016 Cumulative Update 14 | 15.01.0 |
| Microsoft | Microsoft Exchange Server 2016 Cumulative Update 15 | 15.01.0 |
| Microsoft | Microsoft Exchange Server 2016 Cumulative Update 16 | 15.01.0 |
| Microsoft | Microsoft Exchange Server 2016 Cumulative Update 17 | 15.01.0 |
| Microsoft | Microsoft Exchange Server 2016 Cumulative Update 18 | 15.01.0 |
| Microsoft | Microsoft Exchange Server 2016 Cumulative Update 19 | 15.01.0 |
| Microsoft | Microsoft Exchange Server 2016 Cumulative Update 8 | 15.01.0 |
| Microsoft | Microsoft Exchange Server 2016 Cumulative Update 9 | 15.01.0 |
| Microsoft | Microsoft Exchange Server 2019 | 15.02.0 |
| Microsoft | Microsoft Exchange Server 2019 Cumulative Update 1 | 15.02.0 |
| Microsoft | Microsoft Exchange Server 2019 Cumulative Update 2 | 15.02.0 |
…and 33 more
Timeline
- Mar 2, 2021 VulnCheck KEV Exploitation (1154 in total, the first dated here)
- Mar 2, 2021 PoC Published (65 in total, the first dated here)
- Mar 2, 2021 CVE Published
- Mar 6, 2021 VulnCheck XDB Entry (69 in total, the first dated here)
- Apr 14, 2021 EPSS Score (30 in total, the first dated here)
- Nov 3, 2021 CISA KEV Added
- Feb 22, 2026 Security Advisory (24 in total, the first dated here)
- Aug 7, 2026 Coalition ESS Score
- Aug 19, 2026 CVE Updated
Query this with the API
The same record, from the CLI:
vulnetix vdb vuln CVE-2021-26857
vulnetix vdb fixes CVE-2021-26857Or with curl, using the org id and key from your account page:
curl -s -H "Authorization: ApiKey ${VULNETIX_ORG_ID}:${VULNETIX_API_KEY}" \
"https://api.vdb.vulnetix.com/v2/vuln/CVE-2021-26857/fixes/registry"The Community plan is free and allows 50 queries a day. Get a free API key · API quickstart
References
- Microsoft Exchange Server Remote Code Execution Vulnerability vendor-advisorypatch
- https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-26857 advisory
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-26857 advisory
- [MàJ] Multiples vulnérabilités dans Microsoft Exchange Server advisory
- Next-Gen WAF for Microsoft Exchange | Fastly third-party-analysis