CVE-2026-40372

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.
• AutomatableyesAn attacker can reliably automate reconnaissance through exploitation, so this scales.
• Technical ImpacttotalSuccessful exploitation gives total 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

11.20% probability of exploitation activity in the next 30 days.

EPSS percentile

Equal to or higher than the score of 95.9% of scored records. A rank, not a probability.

NVD base score

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

NVD CVSS vector

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

NVD analysis status

Modified. NVD last modified this record on 2026-10-26.

Red Hat severity

Critical. Red Hat's rating for its own products, not a CVSS rating.

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

2026-04-21 19:20Z6 MO AGO

Last updated

2026-10-15 15:53Z13 DAYS AGO

Reserved

2026-04-11

Assigning CNA

microsoft

Record state

PUBLISHED

Severity

Critical (CVSS 9.1)

CNA CVSS vector

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

Weaknesses

• CWE-347Improper Verification of Cryptographic SignatureBase

Data version

5.2

Document digest

395bc91f257f322e1da8d5bc8cf40f4e72b6e18da4e13c88332f0bcaa2eebc83

• msrc.microsoft.comASP.NET Core Elevation of Privilege Vulnerabilityhttps://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-40372vendor-advisorypatch
• access.redhat.comhttps://access.redhat.com/security/cve/CVE-2026-40372vdb-entryx_refsource_REDHAT
• bugzilla.redhat.comRHBZ#2460224https://bugzilla.redhat.com/show_bug.cgi?id=2460224issue-trackingx_refsource_REDHAT
• security.access.redhat.comhttps://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-40372.jsonx_sadp-csaf-vex