CVE-2026-45447 remediation guide

OpenSSL OpenSSL, Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 8

Issue summary: A specially crafted PKCS#7 or S/MIME signed message could trigger a use-after-free during PKCS#7 signature verification. Impact summary: A use-after-free may result in process crashes, heap corruption, or potentially remote code execution. When processing a PKCS#7 or S/MIME signed message, if the SignedData digestAlgorithms field is present as an empty ASN.1 SET, OpenSSL may incorrectly free a caller-owned BIO during PKCS7_verify(). A subsequent use of the BIO by the calling application results in a use-after-free condition. In the common case this occurs when the application...

Open CVE record

ProductOpenSSL OpenSSL, Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 8

Affected versions>= 4.0.0 < 4.0.1, >= 3.6.0 < 3.6.3, >= 3.5.0 < 3.5.7, >= 3.4.0 < 3.4.6, >= 3.0.0 < 3.0.21, >= 1.1.1 < 1.1.1zh, >= 1.0.2 < 1.0.2zq, 4.0.0

Fixed versions1.0.2zq, 1.1.1zh, 3.0.21, 3.4.6, 3.5.7, 3.6.3

Priority basisReview · CVSS 8.8 · EPSS 5.24%

Identify the affected asset

Confirm whether OpenSSL OpenSSL, Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 8 is installed, record the deployed version and installation path, and identify exposed interfaces.

Record the product name, package or appliance identifier, and installed version.
Identify internet-facing, administrative, API, and internal access paths.
Preserve the pre-change configuration and relevant service logs.

Validate the affected-version match

Compare the deployed version with the affected range: >= 4.0.0 < 4.0.1, >= 3.6.0 < 3.6.3, >= 3.5.0 < 3.5.7, >= 3.4.0 < 3.4.6, >= 3.0.0 < 3.0.21, >= 1.1.1 < 1.1.1zh, >= 1.0.2 < 1.0.2zq, 4.0.0. Treat incomplete inventory results as unresolved.

Prioritize with independent signals

The CVSS severity warrants an early asset and exposure review. Combine this signal with asset criticality, exposure, compensating controls, and business impact.

Apply supported remediation

Follow the vendor advisory or supported update path. Current fixed-version status: 1.0.2zq, 1.1.1zh, 3.0.21, 3.4.6, 3.5.7, 3.6.3. Preserve configuration and rollback material before change.

Verify the result

Confirm the resulting version, service health, authentication and access paths, monitoring coverage, and relevant security logs.

Confirm the expected version and package state.
Run a functional health check for critical service paths.
Review authentication, error, application, and security monitoring logs.
Reassess exposure if the supported fix cannot be applied.

Operational boundary

This page does not replace the vendor advisory, support contract, change-management process, or recovery plan. Do not infer that an asset is unaffected from an incomplete inventory query or a missing fixed-version field.