How severe is CVE-2020-0688?

CVE-2020-0688 has a CVSS 3.x base score of 8.8, rated high severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2020-0688 being actively exploited?

Yes. CVE-2020-0688 is on CISA's Known Exploited Vulnerabilities (KEV) catalog, added on 2021-11-03, which means active exploitation has been confirmed. It should be prioritised for remediation.

What products are affected by CVE-2020-0688?

CVE-2020-0688 primarily affects Microsoft Exchange Server. In total, 6 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2020-0688?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Because this CVE is known to be actively exploited, treat remediation as urgent — CISA KEV typically sets a short remediation deadline.

Does CVE-2020-0688 have an EU (EUVD) identifier?

Yes. CVE-2020-0688 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2020-2181. It is also flagged as exploited in the EUVD (since 2021-11-03).

When was CVE-2020-0688 published?

CVE-2020-0688 was published on 2020-02-11 and last updated on 2026-06-17.

CVE-2020-0688

CVE-2020-0688 is a high-severity vulnerability in Microsoft Exchange Server with a CVSS 3.x base score of 8.8. It is listed in CISA's Known Exploited Vulnerabilities (KEV) catalog, confirming it has been exploited in the wild (added 2021-11-03). The underlying weakness is classified as CWE-287.

Key facts

Severity: High (CVSS 3.x base score 8.8)
CVSS v2: 9.0
EPSS exploit prediction: 100% (100th percentile)
Actively exploited: Yes — listed in CISA KEV (added 2021-11-03)
EU (EUVD) id: EUVD-2020-2181
EU exploitation: Flagged exploited in the ENISA EU Vulnerability Database (since 2021-11-03)
Weakness: CWE-287
Affected product: Microsoft Exchange Server
Published: 2020-02-11
Last modified: 2026-06-17

Description

A remote code execution vulnerability exists in Microsoft Exchange software when the software fails to properly handle objects in memory, aka 'Microsoft Exchange Memory Corruption Vulnerability'.

Frequently asked questions

What is CVE-2020-0688?: A remote code execution vulnerability exists in Microsoft Exchange software when the software fails to properly handle objects in memory, aka 'Microsoft Exchange Memory Corruption Vulnerability'.
How severe is CVE-2020-0688?: CVE-2020-0688 has a CVSS 3.x base score of 8.8, rated high severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2020-0688 being actively exploited?: Yes. CVE-2020-0688 is on CISA's Known Exploited Vulnerabilities (KEV) catalog, added on 2021-11-03, which means active exploitation has been confirmed. It should be prioritised for remediation.
What products are affected by CVE-2020-0688?: CVE-2020-0688 primarily affects Microsoft Exchange Server. In total, 6 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2020-0688?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Because this CVE is known to be actively exploited, treat remediation as urgent — CISA KEV typically sets a short remediation deadline.
Does CVE-2020-0688 have an EU (EUVD) identifier?: Yes. CVE-2020-0688 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2020-2181. It is also flagged as exploited in the EUVD (since 2021-11-03).
When was CVE-2020-0688 published?: CVE-2020-0688 was published on 2020-02-11 and last updated on 2026-06-17.

References

Affected products (6)

cpe:2.3:a:microsoft:exchange_server:2010:sp3_rollup_30:*:*:*:*:*:*
cpe:2.3:a:microsoft:exchange_server:2013:cumulative_update_23:*:*:*:*:*:*
cpe:2.3:a:microsoft:exchange_server:2016:cumulative_update_14:*:*:*:*:*:*
cpe:2.3:a:microsoft:exchange_server:2016:cumulative_update_15:*:*:*:*:*:*
cpe:2.3:a:microsoft:exchange_server:2019:cumulative_update_3:*:*:*:*:*:*
cpe:2.3:a:microsoft:exchange_server:2019:cumulative_update_4:*:*:*:*:*:*

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