Red Hat Fixes crun Host-Privilege Exposure on RHEL 9

P1 — VALIDATE AND UPDATEHigh (CVSS); Important (Red Hat impact) · 7.8 maximum (official CVSS v3.1 base score)EXPLOITATION: NOT STATED

Quick Answer

Apply RHSA-2026:97561 to applicable RHEL 9 systems using the entitled repository. Inventory rootful krun and passt use, update the runtime and test representative container starts and networking. Review host activity if untrusted workloads used the affected configuration.

Confirm Scope And Apply The Supported Remediation

What to do now: Record OS release, enabled repositories, architecture, installed crun packages, application dependencies and owners. Match the advisory product tree and fixed package identifiers to the system. Do not generalize the fixed source build to another RHEL stream, architecture or separately bundled copy. Install the supported binary package updates for RHSA-2026:97561 from the entitled Red Hat repositories. Retain the full epoch, version, release and architecture; the source build reference is not an instruction to install an SRPM. Inventory rootful krun and passt use, update the runtime and test representative container starts and networking. Review host activity if untrusted workloads used the affected configuration.

Open the authoritative advisory

Last verified: 2026-11-10 UTC. Recheck the authoritative advisory and supported distribution channel before changing production.

Scope And Authority

Product scopecrun packages on Red Hat Enterprise Linux 9
AdvisoryRHSA-2026:97561
CVECVE-2026-84042
Authoritative release dateNovember 10, 2026 at 15:17:57 UTC, from Red Hat CSAF initial_release_date.
Authority revision dateLast substantive update recorded: 2026-11-10T15:17:57+00:00. CSAF generation timestamp: 2026-11-10T15:18:46+00:00; generation alone is not a material revision.
Affected versionsPackage and architecture combinations identified by RHSA-2026:97561 in Red Hat Enterprise Linux AppStream (v. 9). Red Hat does not state a universal lower affected-version boundary; confirm advisory applicability in the entitled repository.
Fixed versionBinary packages corresponding to source build crun-0:1.29.1-1.el9
CVSS base score7.8 maximum (official CVSS v3.1 base score)
CVSS severityHigh (CVSS); Important (Red Hat impact)
Exploitation statusRed Hat does not state malicious exploitation in this advisory.; no exploitation claim is inferred.

What Changed

The crun update corrects a rootful krun configuration with passt that can execute a container payload as host root. Applicability depends on this runtime and networking combination.

What To Validate Now

  1. Inventory. Record OS release, enabled repositories, architecture, installed crun packages, application dependencies and owners.
  2. Establish applicability. Match the advisory product tree and fixed package identifiers to the system. Do not generalize the fixed source build to another RHEL stream, architecture or separately bundled copy.
  3. Remediate. Install the supported binary package updates for RHSA-2026:97561 from the entitled Red Hat repositories. Retain the full epoch, version, release and architecture; the source build reference is not an instruction to install an SRPM.
  4. Validate. Inventory rootful krun and passt use, update the runtime and test representative container starts and networking. Review host activity if untrusted workloads used the affected configuration.
  5. 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

Review Red Hat prerequisites and plan service availability before rollout. Validate running consumers and restart affected processes where required by the supported change procedure. Severity does not establish exploitation or customer applicability.

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.

Official Per-CVE Scores

  • CVE-2026-84042: 7.8 HIGH (CVSS v3.1).