CriticalFix available

xen — security advisory

Type: advisorySources: OSVAdvisory ID: DEBIAN-CVE-2025-27466

[This CNA information record relates to multiple CVEs; the text explains which aspects/vulnerabilities correspond to which CVE.] There are multiple issues related to the handling and accessing of guest memory pages in the viridian code: 1. A NULL pointer dereference in the updating of the reference TSC area. This is CVE-2025-27466. 2. A NULL pointer dereference by assuming the SIM page is mapped when a synthetic timer message has to be delivered. This is CVE-2025-58142. 3. A race in the mapping of the reference TSC page, where a guest can get Xen to free a page while still present in the guest physical to machine (p2m) page tables. This is CVE-2025-58143.

Products: xen
Affected versions: 4.17.1+2-gb773c48e36-1, 4.17.2+55-g0b56bed864-1, 4.17.2+76-ge1f9cb16e2-1, 4.17.2+76-ge1f9cb16e2-1~deb12u1, 4.17.2-1, 4.17.3+10-g091466ba55-1, 4.17.3+10-g091466ba55-1.1, 4.17.3+10-g091466ba55-1.1~exp1, 4.17.3+10-g091466ba55-1.1~exp2, 4.17.3+10-g091466ba55-1~deb12u1, 4.17.3+36-g54dacb5c02-1, 4.17.5+23-ga4e5191dc0-1, 4.17.5+23-ga4e5191dc0-1+deb12u1, 4.20.0+68-g35cb38b222-1
Fixed versions: 4.17.5+72-g01140da4e8-1, 4.20.2+7-g1badcf5035-0+deb13u1, 4.20.2+7-g1badcf5035-1
CVEs: CVE-2025-27466
Confirmed fixed CVEs: Not specified
Updated in this feed: 31 Oct 2026, 22:32 UTC · Revision 1

Source evidence

DEBIAN-CVE-2025-27466

core-osv · Original source

Published 11 Sept 2025, 14:15 UTC

osv:DEBIAN-CVE-2025-27466

xen

Fixed versions: 4.17.5+72-g01140da4e8-1

xen

Fixed versions: 4.20.2+7-g1badcf5035-0+deb13u1

xen

Fixed versions: 4.20.2+7-g1badcf5035-1

Complete source record

{
  "id": "b33049abc973a582e764fa70f832aff30436a47bfa72ecdd74e25bffc1ef8073",
  "url": "https://osv.dev/vulnerability/DEBIAN-CVE-2025-27466",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "DEBIAN-CVE-2025-27466",
    "summary": "[This CNA information record relates to multiple CVEs; the text explains which aspects/vulnerabilities correspond to which CVE.] There are multiple issues related to the handling and accessing of guest memory pages in the viridian code: 1. A NULL pointer dereference in the updating of the reference TSC area. This is CVE-2025-27466. 2. A NULL pointer dereference by assuming the SIM page is mapped when a synthetic timer message has to be delivered. This is CVE-2025-58142. 3. A race in the mapping of the reference TSC page, where a guest can get Xen to free a page while still present in the guest physical to machine (p2m) page tables. This is CVE-2025-58143.",
    "evidence": "osv:DEBIAN-CVE-2025-27466",
    "products": [
      {
        "name": {
          "value": "xen",
          "evidence": "/affected/0/package/name"
        },
        "prerequisites": [],
        "fixed_versions": [
          {
            "value": "4.17.5+72-g01140da4e8-1",
            "evidence": "/affected/0/ranges"
          }
        ],
        "affected_versions": [
          {
            "value": "4.17.1+2-gb773c48e36-1",
            "evidence": "/affected/0/versions"
          },
          {
            "value": "4.17.2+55-g0b56bed864-1",
            "evidence": "/affected/0/versions"
          },
          {
            "value": "4.17.2+76-ge1f9cb16e2-1",
            "evidence": "/affected/0/versions"
          },
          {
            "value": "4.17.2+76-ge1f9cb16e2-1~deb12u1",
            "evidence": "/affected/0/versions"
          },
          {
            "value": "4.17.2-1",
            "evidence": "/affected/0/versions"
          },
          {
            "value": "4.17.3+10-g091466ba55-1",
            "evidence": "/affected/0/versions"
          },
          {
            "value": "4.17.3+10-g091466ba55-1.1",
            "evidence": "/affected/0/versions"
          },
          {
            "value": "4.17.3+10-g091466ba55-1.1~exp1",
            "evidence": "/affected/0/versions"
          },
          {
            "value": "4.17.3+10-g091466ba55-1.1~exp2",
            "evidence": "/affected/0/versions"
          },
          {
            "value": "4.17.3+10-g091466ba55-1~deb12u1",
            "evidence": "/affected/0/versions"
          },
          {
            "value": "4.17.3+36-g54dacb5c02-1",
            "evidence": "/affected/0/versions"
          },
          {
            "value": "4.17.5+23-ga4e5191dc0-1",
            "evidence": "/affected/0/versions"
          },
          {
            "value": "4.17.5+23-ga4e5191dc0-1+deb12u1",
            "evidence": "/affected/0/versions"
          }
        ]
      },
      {
        "name": {
          "value": "xen",
          "evidence": "/affected/1/package/name"
        },
        "prerequisites": [],
        "fixed_versions": [
          {
            "value": "4.20.2+7-g1badcf5035-0+deb13u1",
            "evidence": "/affected/1/ranges"
          }
        ],
        "affected_versions": [
          {
            "value": "4.20.0+68-g35cb38b222-1",
            "evidence": "/affected/1/versions"
          }
        ]
      },
      {
        "name": {
          "value": "xen",
          "evidence": "/affected/2/package/name"
        },
        "prerequisites": [],
        "fixed_versions": [
          {
            "value": "4.20.2+7-g1badcf5035-1",
            "evidence": "/affected/2/ranges"
          }
        ],
        "affected_versions": [
          {
            "value": "4.20.0+68-g35cb38b222-1",
            "evidence": "/affected/2/versions"
          }
        ]
      }
    ],
    "severity": "critical",
    "structured": {
      "id": "DEBIAN-CVE-2025-27466",
      "aliases": [
        "DEBIAN-CVE-2025-27466"
      ],
      "metrics": [
        {
          "type": "CVSS_V3",
          "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H"
        }
      ],
      "affected": [
        {
          "ranges": [
            {
              "type": "ECOSYSTEM",
              "events": [
                {
                  "introduced": "0"
                },
                {
                  "fixed": "4.17.5+72-g01140da4e8-1"
                }
              ]
            }
          ],
          "package": {
            "name": "xen",
            "purl": "pkg:deb/debian/xen?arch=source&distro=bookworm",
            "ecosystem": "Debian:12"
          },
          "versions": [
            "4.17.1+2-gb773c48e36-1",
            "4.17.2+55-g0b56bed864-1",
            "4.17.2+76-ge1f9cb16e2-1",
            "4.17.2+76-ge1f9cb16e2-1~deb12u1",
            "4.17.2-1",
            "4.17.3+10-g091466ba55-1",
            "4.17.3+10-g091466ba55-1.1",
            "4.17.3+10-g091466ba55-1.1~exp1",
            "4.17.3+10-g091466ba55-1.1~exp2",
            "4.17.3+10-g091466ba55-1~deb12u1",
            "4.17.3+36-g54dacb5c02-1",
            "4.17.5+23-ga4e5191dc0-1",
            "4.17.5+23-ga4e5191dc0-1+deb12u1"
          ],
          "database_specific": {
            "source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2025-27466.json"
          },
          "ecosystem_specific": {
            "urgency": "not yet assigned"
          }
        },
        {
          "ranges": [
            {
              "type": "ECOSYSTEM",
              "events": [
                {
                  "introduced": "0"
                },
                {
                  "fixed": "4.20.2+7-g1badcf5035-0+deb13u1"
                }
              ]
            }
          ],
          "package": {
            "name": "xen",
            "purl": "pkg:deb/debian/xen?arch=source&distro=trixie",
            "ecosystem": "Debian:13"
          },
          "versions": [
            "4.20.0+68-g35cb38b222-1"
          ],
          "database_specific": {
            "source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2025-27466.json"
          },
          "ecosystem_specific": {
            "urgency": "not yet assigned"
          }
        },
        {
          "ranges": [
            {
              "type": "ECOSYSTEM",
              "events": [
                {
                  "introduced": "0"
                },
                {
                  "fixed": "4.20.2+7-g1badcf5035-1"
                }
              ]
            }
          ],
          "package": {
            "name": "xen",
            "purl": "pkg:deb/debian/xen?arch=source&distro=forky",
            "ecosystem": "Debian:14"
          },
          "versions": [
            "4.20.0+68-g35cb38b222-1"
          ],
          "database_specific": {
            "source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2025-27466.json"
          },
          "ecosystem_specific": {
            "urgency": "not yet assigned"
          }
        }
      ],
      "modified": "2026-10-23T17:47:23.785635572Z",
      "provider": "osv",
      "upstream": [
        "CVE-2025-27466"
      ],
      "references": [
        "https://security-tracker.debian.org/tracker/CVE-2025-27466"
      ]
    },
    "related_cves": [
      {
        "value": "CVE-2025-27466",
        "evidence": "/upstream"
      }
    ],
    "security_relevant": true,
    "severity_evidence": "/severity/0/score"
  },
  "source_id": "core-osv",
  "document_id": 416691,
  "published_at": "2025-09-11T14:15:41.413+00:00"
}