{"id":"CVE-2026-121876","aliases":[],"cve":{"records":[{"id":"CVE-2026-121876","source":"redhat","state":"PUBLISHED","reasons":[],"replacements":[],"disputed":false,"unsupportedWhenAssigned":false,"reserved":"2026-11-04T10:34:49.034Z","published":"2026-11-12T16:55:35.424Z","modified":"2026-11-12T18:49:52.690Z"}],"publishers":[{"name":"redhat","role":"CNA","organizationId":"53f830b8-0a3f-465b-8143-3b8a9948e749","modified":"2026-11-12T18:49:52.690Z"}],"references":[{"url":"https://access.redhat.com/security/cve/CVE-2026-121876","tags":["vdb-entry","x_refsource_REDHAT"],"source":"redhat"},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=2558210","tags":["issue-tracking","x_refsource_REDHAT"],"source":"redhat"}],"weaknesses":[{"id":"CWE-359","description":"Exposure of Private Personal Information to an Unauthorized Actor","source":"redhat"}],"applicability":[],"prioritization":[]},"title":"Sandboxed-containers: kernel: systemd-gpt-auto-generator: guest data leakage in confidential computing (sandboxed containers)","titleSource":"redhat","descriptionSource":"redhat","description":"A flaw was found in the interaction between systemd-gpt-auto-generator and \nconfidential computing guest VM images in OpenShift Sandboxed Containers \n(confidential peer pods). systemd-gpt-auto-generator automatically discovers \nand mounts GPT partitions by type GUID at boot with no user confirmation. In \nthe confidential computing threat model, where the host/hypervisor is the \nadversary, a malicious host can inject partitions into the guest's virtual \ndisk. Most critically, injecting a swap partition causes the guest kernel to \npage out TEE-encrypted memory to a host-controlled block device, breaking the \nconfidentiality guarantee of the hardware TEE (AMD SEV-SNP, Intel TDX).\n\nThe PodVM images use a GPT-partitioned disk with dm-verity on the root \npartition. However, the roothash= kernel parameter only disables root \nauto-discovery — non-root partitions (swap, /home, /var, /srv, /var/tmp) are \nstill auto-discovered and mounted. The generator is shipped unmasked in the \nRHEL systemd-udev subpackage, and no kernel command line parameter in the \nmeasured UKI addon disables it. Additionally, the PodVM measurement script \ncaptures PCRs 3, 9, 11, and 12, but not PCR 5 (GPT partition table), so \npartition table modifications are not detected by remote attestation.","score":7.9,"severity":"high","published":"2026-11-12T16:55:35.424Z","modified":"2026-11-12T18:49:52.690Z","withdrawn":false,"knownExploited":false,"affected":[],"products":[{"vendor":"Red Hat","name":"Red Hat Enterprise Linux 10","platforms":[],"versions":[],"defaultStatus":"affected","cpes":["cpe:/a:redhat:enterprise_linux:10"],"source":"redhat","url":"https://www.cve.org/CVERecord?id=CVE-2026-121876"},{"vendor":"Red Hat","name":"Red Hat Enterprise Linux 6","platforms":[],"versions":[],"defaultStatus":"affected","cpes":["cpe:/o:redhat:rhel_els:6"],"source":"redhat","url":"https://www.cve.org/CVERecord?id=CVE-2026-121876"},{"vendor":"Red Hat","name":"Red Hat Enterprise Linux 7","platforms":[],"versions":[],"defaultStatus":"affected","cpes":["cpe:/o:redhat:rhel_els:7"],"source":"redhat","url":"https://www.cve.org/CVERecord?id=CVE-2026-121876"},{"vendor":"Red Hat","name":"Red Hat Enterprise Linux 7","platforms":[],"versions":[],"defaultStatus":"affected","cpes":["cpe:/o:redhat:rhel_els:7"],"source":"redhat","url":"https://www.cve.org/CVERecord?id=CVE-2026-121876"},{"vendor":"Red Hat","name":"Red Hat Enterprise Linux 8","platforms":[],"versions":[],"defaultStatus":"affected","cpes":["cpe:/a:redhat:enterprise_linux:8"],"source":"redhat","url":"https://www.cve.org/CVERecord?id=CVE-2026-121876"},{"vendor":"Red Hat","name":"Red Hat Enterprise Linux 8","platforms":[],"versions":[],"defaultStatus":"affected","cpes":["cpe:/a:redhat:enterprise_linux:8"],"source":"redhat","url":"https://www.cve.org/CVERecord?id=CVE-2026-121876"},{"vendor":"Red Hat","name":"Red Hat Enterprise Linux 9","platforms":[],"versions":[],"defaultStatus":"affected","cpes":["cpe:/a:redhat:enterprise_linux:9"],"source":"redhat","url":"https://www.cve.org/CVERecord?id=CVE-2026-121876"},{"vendor":"Red Hat","name":"Red Hat Enterprise Linux 9","platforms":[],"versions":[],"defaultStatus":"affected","cpes":["cpe:/a:redhat:enterprise_linux:9"],"source":"redhat","url":"https://www.cve.org/CVERecord?id=CVE-2026-121876"},{"vendor":"Red Hat","name":"Red Hat OpenShift Container Platform 4","platforms":[],"versions":[],"defaultStatus":"affected","cpes":["cpe:/a:redhat:openshift:4"],"source":"redhat","url":"https://www.cve.org/CVERecord?id=CVE-2026-121876"},{"vendor":"Red Hat","name":"Red Hat OpenShift Container Platform 4","platforms":[],"versions":[],"defaultStatus":"affected","cpes":["cpe:/a:redhat:openshift:4"],"source":"redhat","url":"https://www.cve.org/CVERecord?id=CVE-2026-121876"},{"vendor":"Red Hat","name":"Red Hat OpenShift Container Platform 5","platforms":[],"versions":[],"defaultStatus":"affected","cpes":["cpe:/a:redhat:openshift:5"],"source":"redhat","url":"https://www.cve.org/CVERecord?id=CVE-2026-121876"}],"remediation":[{"text":"Add systemd.gpt_auto=0 to the measured kernel command line (UKI addon) to completely \ndisable systemd-gpt-auto-generator. Since the PodVM already uses explicit partition \nlayout and dm-verity, auto-discovery is unnecessary.\n\nThe patches released are using the following mitigation: `systemd.image_policy=root=open`.\n\nAlternative mitigations:\n- Disable swap specifically: add systemd.swap=0 to the kernel command line\n- Mask the generator in the guest image: \n  ln -sf /dev/null /etc/systemd/system-generators/systemd-gpt-auto-generator\n- Include PCR 5 in the PodVM measurement script alongside PCRs 3, 9, 11, 12\n- For systemd 254+: set restrictive image policy via systemd.image_policy=root=verity+signed+encrypted+unprotected+absent:swap=absent:home=absent:srv=absent:var=absent:tmp=absent","source":"redhat","url":"https://www.cve.org/CVERecord?id=CVE-2026-121876"}],"references":["https://access.redhat.com/security/cve/CVE-2026-121876","https://bugzilla.redhat.com/show_bug.cgi?id=2558210"],"sources":[{"name":"CVE","id":"CVE-2026-121876","modified":"2026-11-12T18:49:52.690Z","url":"https://www.cve.org/CVERecord?id=CVE-2026-121876"}],"assessments":[{"source":"redhat","vector":"CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:N","score":7.9}],"sourceAffected":[],"observedAt":"2026-11-12T19:38:53.603Z","kev":{"status":"not-listed","checkedAt":"2026-11-15T05:10:35.708Z"},"coverage":[{"source":"NVD","status":"available","checkedAt":"2026-11-12T19:45:53.279Z","attemptedAt":"2026-11-12T19:45:53.279Z"},{"source":"GHSA","status":"available","checkedAt":"2026-11-12T19:45:33.870Z","attemptedAt":"2026-11-12T19:45:33.870Z"},{"source":"EUVD","status":"available","checkedAt":"2026-11-12T19:45:33.786Z","attemptedAt":"2026-11-12T19:45:33.786Z"},{"source":"EPSS","status":"no-result","checkedAt":"2026-11-12T19:45:33.595Z","attemptedAt":"2026-11-12T19:45:33.595Z"}],"evidence":[{"source":"ENISA EUVD","id":"EUVD-2026-124550","url":"https://euvd.enisa.europa.eu/vulnerability/EUVD-2026-124550","modified":"Nov 12, 2026, 6:31:47 PM","score":7.9,"vector":"CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:N","checkedAt":"2026-11-12T19:45:33.786Z"},{"source":"GitHub Advisory Database","id":"GHSA-pvr5-j3rg-w9p8","url":"https://github.com/advisories/GHSA-pvr5-j3rg-w9p8","modified":"2026-11-12T18:31:52Z","score":7.9,"vector":"CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:N","checkedAt":"2026-11-12T19:45:33.870Z"},{"source":"NVD","id":"CVE-2026-121876","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-121876","modified":"2026-11-12T17:17:29.170","score":7.9,"vector":"CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:N","checkedAt":"2026-11-12T19:45:53.279Z"}],"aiSummary":null}