CVE-2025-21259

CVE-2025-21259 is a medium-severity vulnerability in Microsoft Outlook with a CVSS 3.x base score of 5.3. 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-451.

Key facts

Description

Microsoft Outlook Spoofing Vulnerability

Frequently asked questions

What is CVE-2025-21259?
Microsoft Outlook Spoofing Vulnerability
How severe is CVE-2025-21259?
CVE-2025-21259 has a CVSS 3.x base score of 5.3, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity low, and availability none.
Is CVE-2025-21259 being actively exploited?
It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (61st percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2025-21259?
CVE-2025-21259 affects Microsoft Outlook. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2025-21259?
Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2025-21259 have an EU (EUVD) identifier?
Yes. CVE-2025-21259 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-2325.
When was CVE-2025-21259 published?
CVE-2025-21259 was published on 2025-02-11 and last updated on 2026-06-17.

References

Affected products (1)

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