AUGUST 31, 2026
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Case File

CVE-2026-42765

HIGH · CVSS 7.5 EPSS 0.51% Public Exploit

Source: NVD + CISA KEV + EPSS (historical backfill) · Published 2026-06-09 · Last synced 2026-08-04

CyberRota Analysis

This is a high severity vulnerability with a CVSS score of 7.5. It affects OpenSSL. Public exploit code or proof-of-concept references have been detected in its references. It may lead to a denial-of-service condition.

Public Exploit Signal

A public exploit, PoC, GitHub repository or Metasploit reference was detected for this CVE.

Note: these links are listed for security research and verification purposes only.

CVE
CVE-2026-42765
Severity
HIGH
CVSS
7.5
EPSS
0.51%
OpenSSL

Original NVD Description

Issue summary: When a partial-chain certificate verification is enabled together with OCSP response checking for the whole chain, a NULL dereference will happen if the verified chain does not have a self-signed trusted anchor, crashing the process. Impact summary: A NULL pointer dereference can trigger a crash which leads to a Denial of Service for an application. When performing OCSP response checking for certificates in the verification chain, the code always tries to access the next certificate as the issuer. There is a check for a self-signed certificate. However with the partial chain verification enabled when the chain does not have a self-signed trusted anchor, the issuer will be NULL for the last certificate in the chain. A NULL pointer dereference then happens. This issue affects only applications which enable both OCSP verification of the certificate chain (X509_V_FLAG_OCSP_RESP_CHECK_ALL) and partial chain verification (X509_V_FLAG_PARTIAL_CHAIN) in the certificate verification. Both flags are disabled by default. For that reason, we have assigned Low severity to the issue. No FIPS modules are affected by this issue as the affected code is outside the OpenSSL FIPS module boundary.

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