# CVE-2026-63622: Libvirt: swtpm privilege escalation via symlink following

Status: published. Published: 2026-08-10. Updated: 2026-11-03.

A flaw was found in libvirt. A local attacker, specifically a process running as the confined `swtpm` user, could exploit a symlink-following vulnerability in the `virFileChownFiles()` function. By planting a symbolic link within the `swtpm` state directory, the attacker could trick the root-level libvirt daemon into changing the ownership of an arbitrary file to the `swtpm` user. This allows for privilege escalation from the `swtpm` sandbox to root-level file ownership control.

## Remediation

- workaround: If virtual Trusted Platform Module (vTPM) functionality is not required, remove the <tpm> device definition from the domain XML configuration to prevent the vulnerable code path from being reached.

To check if a domain uses vTPM:
```
virsh dumpxml <domain> | grep -A5 '<tpm'
```

To remove it, edit the domain XML and delete the <tpm> block. This prevents libvirt from spawning swtpm processes and from calling virFileChownFiles() on the swtpm state directory during domain startup. Domains that require vTPM for guest OS functionality cannot use this mitigation and should prioritize applying the upstream fix. (source: CNA: redhat)

## Affected products and versions

- Red Hat / Red Hat Enterprise Linux 10 (libvirt): ≥ 0:11.10.0-12.9.el10_2; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 10.0 Extended Update Support (libvirt): ≥ 0:10.10.0-8.11.el10_0; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 7 Extended Lifecycle Support (libvirt): ≥ 0:4.5.0-36.el7_9.7; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 8.4 Advanced Mission Critical Update Support (virt:rhel): ≥ 8040020260916092751.522a0ee4; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 8.4 Extended Update Support Long-Life Add-On (virt:rhel): ≥ 8040020260916092751.522a0ee4; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 8.6 Advanced Mission Critical Update Support (virt:rhel): ≥ 8060020260910092451.ad008a3a; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 8.6 Extended Update Support Long-Life Add-On (virt:rhel): ≥ 8060020260910092451.ad008a3a; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 8.8 Telecommunications Update Service (virt:rhel): ≥ 8080020260910092120.63b34585; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 8.8 Update Services for SAP Solutions (virt:rhel): ≥ 8080020260910092120.63b34585; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 9 (libvirt): ≥ 0:11.10.0-12.7.el9_8; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 9.2 Update Services for SAP Solutions (libvirt): ≥ 0:9.0.0-10.16.el9_2; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 9.4 Update Services for SAP Solutions (libvirt): ≥ 0:10.0.0-6.23.el9_4; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 9.6 Extended Update Support (libvirt): ≥ 0:10.10.0-7.18.el9_6; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 6 (libvirt): Version range not reported. Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 8 (virt:rhel/libvirt): Version range not reported. Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux for NVIDIA 26 (libvirt): Version range not reported. Source: CNA: redhat

## Severity and prioritization

- CVSS 3.1: 7.8 (high); CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H; source: CNA: redhat

- CISA KEV: No listing in collected sources

- EPSS: 0.14% as of 2026-11-03; percentile 3.53%

- SSVC: exploitation none; automatable no; technical impact total; source ADP: CISA-ADP

- Weaknesses: CWE-59

## Exploit evidence

No exploit evidence in collected sources. This is not proof of no exploitation.

## References

- https://access.redhat.com/errata/RHSA-2026:64773 (CNA: redhat; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/errata/RHSA-2026:65515 (CNA: redhat; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/errata/RHSA-2026:65516 (CNA: redhat; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/errata/RHSA-2026:65803 (CNA: redhat; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/errata/RHSA-2026:68513 (CNA: redhat; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/errata/RHSA-2026:68594 (CNA: redhat; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/errata/RHSA-2026:69114 (CNA: redhat; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/errata/RHSA-2026:69131 (CNA: redhat; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/errata/RHSA-2026:74424 (CNA: redhat; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/errata/RHSA-2026:75583 (CNA: redhat; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/security/cve/CVE-2026-63622 (CNA: redhat; vdb-entry, x_refsource_REDHAT)

- https://bugzilla.redhat.com/show_bug.cgi?id=2513065 (CNA: redhat; issue-tracking, x_refsource_REDHAT)

## Provenance

- CNA: redhat: https://www.cve.org/CVERecord?id=CVE-2026-63622; retrieved 2026-11-04; source updated 2026-11-03

- FIRST EPSS: https://api.first.org/data/v1/epss?cve=CVE-2026-63622; retrieved 2026-11-04; source updated Not reported

Revision: fb8b059daea6b8e72fe0de3bb6ec182bfce7b8a545dfe81fce4115b49e5e4a88

Canonical: https://y2.dev/cve/CVE-2026-63622

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