Red Hat libkcapi Update Addresses Three RHEL 10 Flaws
Tech GuruQuick Answer
Red Hat's RHSA-2026:69285 updates libkcapi on RHEL 10.0 EUS to 1.5.0-6.el10_0. The three CVEs concern repeated initialization vectors in large one-shot cipher operations, outstanding asynchronous writes after an error, and a nonterminating wait when reusing an errored asynchronous handle.
Confirm Scope And Apply The Supported Fix
What to do now: Inventory RHEL 10.0 EUS libkcapi packages, match the exact affected release or feature, apply the authority-supported fixed build or service remediation, validate the dependent workflow, and preserve evidence.
Last verified: 2026-09-21 UTC. Recheck the authoritative advisory and supported distribution channel before changing production.
Scope And Authority
| Product scope | RHEL 10.0 EUS libkcapi packages |
|---|---|
| Advisory | RHSA-2026:69285 |
| CVEs | CVE-2026-71225, CVE-2026-71226, CVE-2026-71227 |
| Authoritative release date | 2026-09-21 12:13:26 UTC |
| Authority revision date | 2026-09-21 12:29:35 UTC |
| Affected versions | The advisory-specific supported RHEL 10.0 EUS libkcapi packages builds before the listed fixed package or release. |
| Fixed version | libkcapi 1.5.0-6.el10_0 |
| CVSS base score | 5.1 / 6.5 / 7.3 (CVSS v3.1) |
| CVSS severity | Medium to High |
| Exploitation status | Not stated by the authority; no exploitation claim is inferred. |
What Changed
CVE-2026-71225 concerns stateful modes such as CTR or CBC on inputs larger than 64 KiB: internal chunks reuse the initialization vector, weakening confidentiality and potentially affecting integrity. CVE-2026-71226 concerns an error return before all asynchronous requests finish, allowing later kernel writes into the caller's output buffers. CVE-2026-71227 concerns reusing an AIO-enabled handle after a completion error, which can leave the application waiting indefinitely. These conditions require separate application-path checks.
What To Validate Now
- Inventory. Locate RHEL 10.0 EUS libkcapi packages deployments, versions, enabled features, exposure paths, owners, and dependent services.
- Establish applicability. Compare each deployment with the authority's affected-version statement: The advisory-specific supported RHEL 10.0 EUS libkcapi packages builds before the listed fixed package or release. Do not infer applicability from product family or severity alone.
- Remediate. Apply libkcapi 1.5.0-6.el10_0 through the supported vendor or project channel, following the current advisory and change-control requirements.
- Validate. Confirm the fixed library and active consumers, then test approved large-input cipher operations, asynchronous completion/error handling, and supported handle reuse in the application's test environment. Do not infer safety from a single successful small-buffer operation.
- Retain evidence. Preserve asset and owner identifiers, the applicability decision, before-and-after versions, change approval, installation output, validation results, and any exception or rollback record.
Operational Cautions
Use the exact supported release stream and repository. Test dependencies, clusters, integrations, and rollback before broad deployment; a CVSS rating or reachable feature is not evidence of exploitation.
Evidence To Retain
- Exact product, release stream, package or application version, enabled feature, environment, and accountable owner.
- UTC timestamps, authority revision, approved change record, installer or package-manager output, and resulting version.
- Relevant logs and monitoring evidence, test results, exceptions, compensating controls, and rollback decisions.
Related TechGeeks Resources
Authoritative References
Correction policy: If the authority changes affected versions, fixed versions, severity, exploitation information, mitigations, or required action, TechGeeks will update this notice and its verification date.
