CVE-2026-55007 json
Microsoft Exchange Server Remote Code Execution Vulnerability
published 2026-09-08 2 mo ago modified 2026-10-31 8 d ago also EUVD-2026-73178
- cvss
- 8.1
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.7%
- EPSS 0.7% chance of exploitation in 30 days, percentile 53%
- public exploits
- 0
- none known
Summary
Double free in Microsoft Exchange Server allows an unauthorized attacker to execute code over a network.
Patch / fix
- Microsoft Microsoft Exchange Server 2019 Cumulative Update 14 15.02.1544.046
- Microsoft Microsoft Exchange Server 2019 Cumulative Update 15 15.02.1748.051
- Microsoft Microsoft Exchange Server Subscription Edition RTM 15.02.2562.049
CISA SSVC
- Exploitation
- none
- Automatable
- no
- Technical impact
- total
- Assessed
- 2 mo ago
Exploit prediction
0.71% chance of exploitation in the next 30 days, higher than 53% of all scored CVEs (FIRST EPSS, 2026-11-08).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 8.1 | CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C |
| CNA | 3.1 | 8.1 | CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H |
Affected products
- Microsoft Microsoft Exchange Server 2019 Cumulative Update 14
- Microsoft Microsoft Exchange Server 2019 Cumulative Update 15
- Microsoft Microsoft Exchange Server Subscription Edition RTM
Classification
- Weakness
-
- CWE-415 Double Free
- Technology feeds
References
-
msrc.microsoft.com
/update-guide/vulnerability/CVE-2026-55007
vendor-advisory, patch
Sources
- CVE List CVE-2026-55007
- NVD CVE-2026-55007
Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.