How severe is CVE-2018-0833?

CVE-2018-0833 has a CVSS 3.x base score of 5.3, rated medium severity. It is exploitable over network with high attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2018-0833 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 41% (98th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2018-0833?

CVE-2018-0833 primarily affects Microsoft Windows 8.1. In total, 3 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2018-0833?

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

When was CVE-2018-0833 published?

CVE-2018-0833 was published on 2018-02-15 and last updated on 2026-06-17.

CVE-2018-0833

CVE-2018-0833 is a medium-severity vulnerability in Microsoft Windows 8.1 with a CVSS 3.x base score of 5.3. Its EPSS exploit-prediction score of 41% places it in the 98th percentile, indicating an elevated likelihood of exploitation. The underlying weakness is classified as CWE-476.

Key facts

Severity: Medium (CVSS 3.x base score 5.3)
CVSS v2: 6.3
EPSS exploit prediction: 41% (98th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-476
Affected product: Microsoft Windows 8.1
Published: 2018-02-15
Last modified: 2026-06-17

Description

The Microsoft Server Message Block 2.0 and 3.0 (SMBv2/SMBv3) client in Windows 8.1 and RT 8.1 and Windows Server 2012 R2 allows a denial of service vulnerability due to how specially crafted requests are handled, aka "SMBv2/SMBv3 Null Dereference Denial of Service Vulnerability".

Frequently asked questions

What is CVE-2018-0833?: The Microsoft Server Message Block 2.0 and 3.0 (SMBv2/SMBv3) client in Windows 8.1 and RT 8.1 and Windows Server 2012 R2 allows a denial of service vulnerability due to how specially crafted requests are handled, aka "SMBv2/SMBv3 Null Dereference Denial of Service Vulnerability".
How severe is CVE-2018-0833?: CVE-2018-0833 has a CVSS 3.x base score of 5.3, rated medium severity. It is exploitable over network with high attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2018-0833 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 41% (98th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2018-0833?: CVE-2018-0833 primarily affects Microsoft Windows 8.1. In total, 3 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2018-0833?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2018-0833 published?: CVE-2018-0833 was published on 2018-02-15 and last updated on 2026-06-17.

References

Affected products (3)

cpe:2.3:o:microsoft:windows_8.1:-:*:*:*:*:*:*:*
cpe:2.3:o:microsoft:windows_rt_8.1:-:*:*:*:*:*:*:*
cpe:2.3:o:microsoft:windows_server_2012:r2:*:*:*:*:*:*:*

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