CVE-2023-21761
CVE-2023-21761 is a high-severity vulnerability in Microsoft Exchange Server with a CVSS 3.x base score of 7.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-918.
Key facts
- Severity: High (CVSS 3.x base score 7.5)
- EPSS exploit prediction: 2% (73rd percentile)
- Actively exploited: Not listed in CISA KEV
- Weakness: CWE-918
- Affected product: Microsoft Exchange Server
- Published:
- Last modified:
Description
Microsoft Exchange Server Information Disclosure Vulnerability
Frequently asked questions
- What is CVE-2023-21761?
- Microsoft Exchange Server Information Disclosure Vulnerability
- How severe is CVE-2023-21761?
- CVE-2023-21761 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.
- Is CVE-2023-21761 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (73rd percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2023-21761?
- CVE-2023-21761 primarily affects Microsoft Exchange Server. In total, 3 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
- How do I fix CVE-2023-21761?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
- When was CVE-2023-21761 published?
- CVE-2023-21761 was published on 2023-01-10 and last updated on 2026-06-17.
References
Affected products (3)
- cpe:2.3:a:microsoft:exchange_server:2016:cumulative_update_23:*:*:*:*:*:*
- cpe:2.3:a:microsoft:exchange_server:2019:cumulative_update_11:*:*:*:*:*:*
- cpe:2.3:a:microsoft:exchange_server:2019:cumulative_update_12:*:*:*:*:*:*
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