How severe is CVE-2018-0940?

CVE-2018-0940 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is high, integrity none, and availability none.

Is CVE-2018-0940 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 8% (94th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2018-0940?

CVE-2018-0940 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-2018-0940?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2018-0940 published?

CVE-2018-0940 was published on 2018-03-14 and last updated on 2026-06-17.

CVE-2018-0940

CVE-2018-0940 is a medium-severity vulnerability in Microsoft Exchange Server with a CVSS 3.x base score of 6.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low.

Key facts

Severity: Medium (CVSS 3.x base score 6.5)
CVSS v2: 4.3
EPSS exploit prediction: 8% (94th percentile)
Actively exploited: Not listed in CISA KEV
Affected product: Microsoft Exchange Server
Published: 2018-03-14
Last modified: 2026-06-17

Description

Microsoft Exchange Outlook Web Access (OWA) in Microsoft Exchange Server 2010 Service Pack 3 Update Rollup 20, Microsoft Exchange Server 2013 Cumulative Update 18, Microsoft Exchange Server 2013 Cumulative Update 19, Microsoft Exchange Server 2013 Service Pack 1, Microsoft Exchange Server 2016 Cumulative Update 7, and Microsoft Exchange Server 2016 Cumulative Update 8 allows an elevation of privilege vulnerability due to how links in the body of an email message are rewritten, aka "Microsoft Exchange Elevation of Privilege Vulnerability".

Frequently asked questions

What is CVE-2018-0940?: Microsoft Exchange Outlook Web Access (OWA) in Microsoft Exchange Server 2010 Service Pack 3 Update Rollup 20, Microsoft Exchange Server 2013 Cumulative Update 18, Microsoft Exchange Server 2013 Cumulative Update 19, Microsoft Exchange Server 2013 Service Pack 1, Microsoft Exchange Server 2016 Cumulative Update 7, and Microsoft Exchange Server 2016 Cumulative Update 8 allows an elevation of privilege vulnerability due to how links in the body of an email message are rewritten, aka "Microsoft Exchange Elevation of Privilege Vulnerability".
How severe is CVE-2018-0940?: CVE-2018-0940 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is high, integrity none, and availability none.
Is CVE-2018-0940 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 8% (94th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2018-0940?: CVE-2018-0940 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-2018-0940?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2018-0940 published?: CVE-2018-0940 was published on 2018-03-14 and last updated on 2026-06-17.

References

Affected products (6)

cpe:2.3:a:microsoft:exchange_server:2010:sp3_rollup20:*:*:*:*:*:*
cpe:2.3:a:microsoft:exchange_server:2013:cumulative_update_18:*:*:*:*:*:*
cpe:2.3:a:microsoft:exchange_server:2013:cumulative_update_19:*:*:*:*:*:*
cpe:2.3:a:microsoft:exchange_server:2013:sp1:*:*:*:*:*:*
cpe:2.3:a:microsoft:exchange_server:2016:cumulative_update_7:*:*:*:*:*:*
cpe:2.3:a:microsoft:exchange_server:2016:cumulative_update_8:*:*:*:*:*:*

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