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.
CVSS Details
- CVSS 3.1 Base Score: 7.5
- CVSS 3.1 Vector: (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H)
Covered by Rapid7
| Product | Vendor Advisory | Solution File | Added | Published |
|---|---|---|---|---|
| Freebsd | — | Upgrade openssl111Upgrade opensslUpgrade openssl40Upgrade openssl36Upgrade openssl34Upgrade openssl35Upgrade FreeBSD | Jun 15, 2026 | Jun 10, 2026 |
| Http Openssl | — | Upgrade to the latest version of OpenSSL | Jun 10, 2026 | Jun 9, 2026 |
| Vmware Photon_os | — | Use 'tdnf update' to upgrade all packages to the latest version. | Jun 18, 2026 | Jun 9, 2026 |
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