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TI-2026-33273 Aliases CVE-2026-45503GHSA-p44w-fhq3-v2jv

Microsoft Exchange Server Information Disclosure Vulnerability

Priority LOW 38CWE-285Published · Updated

Key facts

Attack vector
Network
Privileges required
Low
User interaction
None
Attack complexity
Low
Impact type
Information disclosure
Confidentiality · integrity · availability
High · High · None
Fix status
Fixed

Attack profile from CVSS 3.1 · CNA. Fix status from CNA and Microsoft. Impact type from Microsoft.

Summary

Improper authorization in Microsoft Exchange Server allows an authorized attacker to disclose information over a network.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00445 38th percentileScored 2026-11-07
Fix Fixed Microsoft: 4 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

VendorProductAffected versionsFixed inStatusSource
MicrosoftMicrosoft Exchange Server 2016 Cumulative Update 2315.01.0.0 to before 15.01.2507.07115.01.2507.071Patch availableCNA
MicrosoftMicrosoft Exchange Server 2019 Cumulative Update 1415.02.0.0 to before 15.02.1544.04315.02.1544.043Patch availableCNA
MicrosoftMicrosoft Exchange Server 2019 Cumulative Update 1515.02.0.0 to before 15.02.1748.04815.02.1748.048Patch availableCNA
MicrosoftMicrosoft Exchange Server Subscription Edition RTM15.02.0.0 to before 15.02.2562.04515.02.2562.045Patch availableCNA
  • Microsoft Exchange Server 2016 Cumulative Update 23 VendorMicrosoft Affected 15.01.0.0 to before 15.01.2507.071 Fixed in 15.01.2507.071 Patch available CNA
  • Microsoft Exchange Server 2019 Cumulative Update 14 VendorMicrosoft Affected 15.02.0.0 to before 15.02.1544.043 Fixed in 15.02.1544.043 Patch available CNA
  • Microsoft Exchange Server 2019 Cumulative Update 15 VendorMicrosoft Affected 15.02.0.0 to before 15.02.1748.048 Fixed in 15.02.1748.048 Patch available CNA
  • Microsoft Exchange Server Subscription Edition RTM VendorMicrosoft Affected 15.02.0.0 to before 15.02.2562.045 Fixed in 15.02.2562.045 Patch available CNA

CPE configurations NVD · 4

CPEVersionsRoleVendor
cpe:2.3:a:microsoft:exchange_server:2016:cumulative_update_23:*:*:*:*:*:*2016 cumulative_update_23VulnerableMicrosoft
cpe:2.3:a:microsoft:exchange_server:2019:cumulative_update_14:*:*:*:*:*:*2019 cumulative_update_14VulnerableMicrosoft
cpe:2.3:a:microsoft:exchange_server:2019:cumulative_update_15:*:*:*:*:*:*2019 cumulative_update_15VulnerableMicrosoft
cpe:2.3:a:microsoft:exchange_server_subscription_edition:*:*:*:*:*:*:*:*before 15.02.2562.043VulnerableMicrosoft
  • cpe:2.3:a:microsoft:exchange_server:2016:cumulative_update_23:*:*:*:*:*:* Versions 2016 cumulative_update_23 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 15.02.2562.043 Vulnerable ·Microsoft

Remediation

Microsoft 4 updates

  • Security Update
    • Microsoft Exchange Server 2016 Cumulative Update 23 15.01.2507.071
  • Security Update
    • Microsoft Exchange Server 2019 Cumulative Update 14 15.02.1544.043
  • Security Update
    • Microsoft Exchange Server 2019 Cumulative Update 15 15.02.1748.048
Show 1 more Microsoft updates
  • Security Update
    • Microsoft Exchange Server Subscription Edition RTM 15.02.2562.045

Vendor assessments

Microsoft

Microsoft's page for this CVE →

Impact
Information Disclosure
Exploited
No
Publicly disclosed
No
Exploitability
Exploitation Unlikely

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-45503
  2. 2026-10-03 Alias added: GHSA-p44w-fhq3-v2jv
  3. 2026-10-25 EPSS moved to the below the 50th percentile

References

  • 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
See all 258 →

Sources