How severe is CVE-2026-69375?

CVE-2026-69375 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity high, and availability none.

Is CVE-2026-69375 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (49th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-69375?

CVE-2026-69375 primarily affects Microsoft Exchange Server. In total, 4 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2026-69375?

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

When was CVE-2026-69375 published?

CVE-2026-69375 was published on 2026-09-08 and last updated on 2026-09-29.

CVE-2026-69375

CVE-2026-69375 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. The underlying weakness is classified as CWE-639.

Key facts

Severity: Medium (CVSS 3.x base score 6.5)
EPSS exploit prediction: 1% (49th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-639
Affected product: Microsoft Exchange Server
Published: 2026-09-08
Last modified: 2026-09-29

Description

Authorization bypass through user-controlled key in Microsoft Exchange Server allows an authorized attacker to perform tampering over a network.

Frequently asked questions

What is CVE-2026-69375?: Authorization bypass through user-controlled key in Microsoft Exchange Server allows an authorized attacker to perform tampering over a network.
How severe is CVE-2026-69375?: CVE-2026-69375 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity high, and availability none.
Is CVE-2026-69375 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (49th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-69375?: CVE-2026-69375 primarily affects Microsoft Exchange Server. In total, 4 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2026-69375?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2026-69375 published?: CVE-2026-69375 was published on 2026-09-08 and last updated on 2026-09-29.

References

https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-69375

Affected products (4)

cpe:2.3:a:microsoft:exchange_server:2016:cumulative_update_23:*:*:*:*:*:*
cpe:2.3:a:microsoft:exchange_server:2019:cumulative_update_14:*:*:*:*:*:*
cpe:2.3:a:microsoft:exchange_server:2019:cumulative_update_15:*:*:*:*:*:*
cpe:2.3:a:microsoft:exchange_server_subscription_edition:*:*:*:*:*:*:*:*

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