Microsoft Exchange Server Remote Code Execution Vulnerability
Priority LOW 38CWE-415Published · Updated
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- None
- Attack complexity
- High
- Impact type
- Code execution
- Confidentiality · integrity · availability
- High · High · High
- Fix status
- Fixed
Attack profile from CVSS 3.1 · CNA. Fix status from CNA and Microsoft. Impact type from Microsoft.
Summary
Double free in Microsoft Exchange Server allows an unauthorized attacker to execute code over a network.
Why it matters now
Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00707 53rd percentileScored 2026-11-07
Fix Fixed Microsoft: 3 updates
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- No
- Technical impact
- Total
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| Microsoft | Microsoft Exchange Server 2019 Cumulative Update 14 | 15.02.0.0 to before 15.02.1544.046 | 15.02.1544.046 | Patch available | CNA |
| Microsoft | Microsoft Exchange Server 2019 Cumulative Update 15 | 15.02.0.0 to before 15.02.1748.051 | 15.02.1748.051 | Patch available | CNA |
| Microsoft | Microsoft Exchange Server Subscription Edition RTM | 15.02.0.0 to before 15.02.2562.049 | 15.02.2562.049 | Patch available | CNA |
- Microsoft Exchange Server 2019 Cumulative Update 14 VendorMicrosoft Affected 15.02.0.0 to before 15.02.1544.046 Fixed in 15.02.1544.046 Patch available CNA
- Microsoft Exchange Server 2019 Cumulative Update 15 VendorMicrosoft Affected 15.02.0.0 to before 15.02.1748.051 Fixed in 15.02.1748.051 Patch available CNA
- Microsoft Exchange Server Subscription Edition RTM VendorMicrosoft Affected 15.02.0.0 to before 15.02.2562.049 Fixed in 15.02.2562.049 Patch available CNA
CPE configurations NVD · 3
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:a:microsoft:exchange_server:2019:cumulative_update_14:*:*:*:*:*:* | 2019 cumulative_update_14 | Vulnerable | Microsoft |
| cpe:2.3:a:microsoft:exchange_server:2019:cumulative_update_15:*:*:*:*:*:* | 2019 cumulative_update_15 | Vulnerable | Microsoft |
| cpe:2.3:a:microsoft:exchange_server_subscription_edition:*:*:*:*:*:*:*:* | before 15.02.2562.049 | Vulnerable | Microsoft |
- cpe:2.3:a:microsoft:exchange_server:2019:cumulative_update_14:*:*:*:*:*:* Versions 2019 cumulative_update_14 Vulnerable ·Microsoft
- cpe:2.3:a:microsoft:exchange_server:2019:cumulative_update_15:*:*:*:*:*:* Versions 2019 cumulative_update_15 Vulnerable ·Microsoft
- cpe:2.3:a:microsoft:exchange_server_subscription_edition:*:*:*:*:*:*:*:* Versions before 15.02.2562.049 Vulnerable ·Microsoft
Remediation
Vendor assessments
Microsoft
Microsoft's page for this CVE →
- Impact
- Remote Code Execution
- Exploited
- No
- Publicly disclosed
- No
- Exploitability
- Exploitation Less Likely
Timeline
- 2026-10-02 Threatist record created from CVE-2026-55007
- 2026-10-03 Alias added: GHSA-phwr-836j-jgp8
References
More Microsoft Exchange Server vulnerabilities
- TI-2024-14170 Microsoft Exchange Server Elevation of Privilege Vulnerability KEVCVSS 3.1CRITICAL 9.8
- TI-2022-19610 Microsoft Exchange Server Elevation of Privilege Vulnerability KEVCVSS 3.1CRITICAL 9.8
- TI-2021-13547 Microsoft Exchange Server Elevation of Privilege Vulnerability KEVCVSS 3.1CRITICAL 9.8
- TI-2021-13502 Microsoft Exchange Server Remote Code Execution Vulnerability KEVCVSS 3.1CRITICAL 9.8
- TI-2021-08465 Microsoft Exchange Server Remote Code Execution Vulnerability KEVCVSS 3.1CRITICAL 9.8
- TI-2023-07929 Microsoft Exchange Server Remote Code Execution Vulnerability KEVCVSS 3.1HIGH 8.8
Sources
- CVE-2026-55007 · CVE Program
- CVE-2026-55007 · NVD
- FIRST EPSS
- GHSA-phwr-836j-jgp8 · GitHub Advisory Database · CC BY 4.0
- CVE-2026-55007 · Microsoft Security Update Guide
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences