Double Free in Openssl
CVE-2026-35188
Issue summary: A malicious server can exploit TLS OCSP stapling by delivering a crafted response through the status_request extension, triggering a double-free in the client's certificate verification path. Impact summary: Successful expl…
Vulnerability class: Double Free
EPSS: 0.003 (22.5th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 5.0 (Medium). Vector: CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:L/A:L.
Affected products
- Openssl — versions 4.0.0, 3.6.0
Weakness classification (CWE)
References
- openssl-security@openssl.org
- openssl-security@openssl.org
- openssl-security@openssl.org (vendor-advisory, Vendor Advisory)
- openssl-security@openssl.org (Patch, patch)
- openssl-security@openssl.org (Patch, patch)
Frequently asked questions
- What is CVE-2026-35188?
- CVE-2026-35188 is a medium-severity vulnerability in Openssl, classified under Double Free. CVSS score: 5.0/10. Published 2026-06-09.
- How severe is CVE-2026-35188?
- Medium severity. CVSS v3 base score is 5.0 out of 10.