CVE-2026-40378
CVSS v3
7.5
HIGH
EPSS Score
1.2 %
exploit probability, as of 2026-09-25
CISA KEV
No
known exploited
Exploitation
—
SSVC status
Description
Memory allocation with excessive size value in Windows Local Security Authority Subsystem Service (LSASS) allows an unauthorized attacker to deny service over a network.
Technical details
- Published
- 2026-07-14
- Last Modified
- 2026-07-14
Frequently asked questions
What is CVE-2026-40378?
Memory allocation with excessive size value in Windows Local Security Authority Subsystem Service (LSASS) allows an unauthorized attacker to deny service over a network.
Is CVE-2026-40378 actively exploited?
Active exploitation of CVE-2026-40378 has not been confirmed. Its EPSS score was 1.2% on 2026-09-25, the estimated probability of exploitation in the next 30 days.
What is the CVSS score for CVE-2026-40378?
CVE-2026-40378 has a CVSS v3 base score of 7.5 (HIGH severity).
Is CVE-2026-40378 affecting your environment?
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