NULL pointer dereference in Openssl

CVE-2026-42766

Issue summary: A specially crafted password-encrypted CMS message can trigger a NULL pointer dereference during CMS decryption. Impact summary: This NULL pointer dereference leads to an application crash and a Denial of Service. The CMS…

EPSS: 0.010 (59.1th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 5.9 (Medium). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H.

Affected products

  • Openssl — versions 4.0.0, 3.6.0, 3.5.0

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-42766?
CVE-2026-42766 is a medium-severity vulnerability in Openssl, classified under NULL Pointer Dereference. CVSS score: 5.9/10. Published 2026-06-09.
How severe is CVE-2026-42766?
Medium severity. CVSS v3 base score is 5.9 out of 10.