CVE-2023-21687

Exploitation

Assessed, none found. CISA's assessment recorded neither public exploit code nor evidence of exploitation when it was made.

SSVC decision

• ExploitationnoneCISA recorded no public exploit code and no evidence of exploitation.
• AutomatablenoAt least one step from reconnaissance to exploitation cannot be reliably automated.
• Technical ImpactpartialSuccessful exploitation gives limited control of the vulnerable component.

CISA publishes the decision points, not a final SSVC decision. The decision also depends on mission and well-being impact, which is a property of your deployment rather than of the vulnerability.

EPSS probability

0.46% probability of exploitation activity in the next 30 days.

EPSS percentile

Equal to or higher than the score of 39.9% of scored records. A rank, not a probability.

NVD base score

5.5 (CVSS v3.x), scored by the NVD independently of the CNA.

NVD CVSS vector

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N

NVD analysis status

Modified. NVD last modified this record on 2026-08-19.

Red Hat severity

No Red Hat rating. Red Hat rates the CVEs that affect its products.

Exploit-prediction scores from FIRST. Independent scoring and analysis status from the NVD. Vendor severity from Red Hat. Exploitation assessment and catalog membership from CISA.

Published

2023-02-14 19:33Z3 YR AGO

Last updated

2026-08-19 16:27Z2 MO AGO

Reserved

2022-12-13

Assigning CNA

microsoft

Record state

PUBLISHED

Severity

Medium (CVSS 5.5)

CNA CVSS vector

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N/E:U/RL:O/RC:C

Weaknesses

• CWE-125Out-of-bounds ReadBase

Data version

5.2

Document digest

3fa734d65c319446e0a0cdff5ac2029d6d836a1d33d0dc09e07dfb9ea31250fb

• msrc.microsoft.comHTTP.sys Information Disclosure Vulnerabilityhttps://msrc.microsoft.com/update-guide/vulnerability/CVE-2023-21687vendor-advisorypatch