Vulnerability-Lookup

ubuntu-cve-2026-48756

Vulnerability from osv_ubuntu

Published

2026-08-21 15:16

Modified

2026-09-02 16:18

Summary

Details

Incus is a system container and virtual machine manager. Prior to version 7.1.0, (*backend).CreateCustomVolumeFromBackup in internal/server/storage/backend.go contains an unguarded *time.Time dereference on the ExpiresAt field of every volume-snapshot entry in an imported custom-volume backup. An authenticated user with can_create_storage_volumes permission on any project can crash the incusd daemon by uploading a backup tarball whose volume_snapshots[*].expires_at field is absent. This is a sibling-field variant of GHSA-r7w7-mmxr-47r9 (CVE-2026-40197). Commit 985a1dedf9f3e7ba729c93b654905ed510de25c2 added if s == nil at the top of the loop body, but did not guard the adjacent *snapshot.ExpiresAt deref 19 lines later. Every other consumer of Config.VolumeSnapshots[i].ExpiresAt in this same file already gates the deref with a nil-check — the asymmetric guard is the bug. Version 7.1.0 contains an updated patch.

Severity

2.1 (Low)


                    
                      CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:P

N/A (UNKNOWN)


                    
                      medium

References

URL

Type

	https://ubuntu.com/security/CVE-2026-48756	REPORT
	https://www.cve.org/CVERecord?id=CVE-2026-48756	REPORT
	https://github.com/lxc/incus/pull/3425	REPORT
	https://github.com/lxc/incus/security/advisories/…	REPORT

JSON

To clipboard

{
  "affected": [
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "golang-github-lxc-lxd-dev",
            "binary_version": "2.0.11-0ubuntu1~16.04.4+esm3"
          },
          {
            "binary_name": "lxc2",
            "binary_version": "2.0.11-0ubuntu1~16.04.4+esm3"
          },
          {
            "binary_name": "lxd",
            "binary_version": "2.0.11-0ubuntu1~16.04.4+esm3"
          },
          {
            "binary_name": "lxd-client",
            "binary_version": "2.0.11-0ubuntu1~16.04.4+esm3"
          },
          {
            "binary_name": "lxd-tools",
            "binary_version": "2.0.11-0ubuntu1~16.04.4+esm3"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:Pro:16.04:LTS",
        "name": "lxd",
        "purl": "pkg:deb/ubuntu/lxd@2.0.11-0ubuntu1~16.04.4+esm3?arch=source\u0026distro=esm-infra-legacy/xenial"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "0.20-0ubuntu4",
        "0.21-0ubuntu3",
        "0.21-0ubuntu5",
        "0.22-0ubuntu1",
        "0.22-0ubuntu2",
        "0.23-0ubuntu1",
        "0.23-0ubuntu2",
        "0.23-0ubuntu3",
        "0.24-0ubuntu2",
        "0.24-0ubuntu3",
        "0.24-0ubuntu4",
        "0.25-0ubuntu1",
        "0.26-0ubuntu2",
        "0.26-0ubuntu3",
        "0.27-0ubuntu1",
        "0.27-0ubuntu2",
        "2.0.0~beta1-0ubuntu3",
        "2.0.0~beta1-0ubuntu4",
        "2.0.0~beta2-0ubuntu1",
        "2.0.0~beta2-0ubuntu2",
        "2.0.0~beta3-0ubuntu1",
        "2.0.0~beta3-0ubuntu2",
        "2.0.0~beta3-0ubuntu3",
        "2.0.0~beta3-0ubuntu4",
        "2.0.0~beta4-0ubuntu1",
        "2.0.0~beta4-0ubuntu2",
        "2.0.0~beta4-0ubuntu3",
        "2.0.0~beta4-0ubuntu4",
        "2.0.0~beta4-0ubuntu5",
        "2.0.0~beta4-0ubuntu6",
        "2.0.0~beta4-0ubuntu7",
        "2.0.0~rc1-0ubuntu1",
        "2.0.0~rc1-0ubuntu2",
        "2.0.0~rc1-0ubuntu3",
        "2.0.0~rc2-0ubuntu2",
        "2.0.0~rc2-0ubuntu3",
        "2.0.0~rc3-0ubuntu1",
        "2.0.0~rc3-0ubuntu2",
        "2.0.0~rc3-0ubuntu3",
        "2.0.0~rc3-0ubuntu4",
        "2.0.0~rc4-0ubuntu1",
        "2.0.0~rc5-0ubuntu1",
        "2.0.0~rc6-0ubuntu1",
        "2.0.0~rc6-0ubuntu2",
        "2.0.0~rc7-0ubuntu1",
        "2.0.0~rc7-0ubuntu2",
        "2.0.0~rc8-0ubuntu1",
        "2.0.0~rc8-0ubuntu2",
        "2.0.0~rc8-0ubuntu3",
        "2.0.0~rc8-0ubuntu5",
        "2.0.0~rc8-0ubuntu6",
        "2.0.0~rc8-0ubuntu7",
        "2.0.0~rc9-0ubuntu2",
        "2.0.0~rc9-0ubuntu3",
        "2.0.0~rc9-0ubuntu4",
        "2.0.0~rc9-0ubuntu5",
        "2.0.0-0ubuntu1",
        "2.0.0-0ubuntu2",
        "2.0.0-0ubuntu3",
        "2.0.0-0ubuntu4",
        "2.0.1-0ubuntu1~16.04.1",
        "2.0.2-0ubuntu1~16.04.1",
        "2.0.3-0ubuntu1~ubuntu16.04.2",
        "2.0.4-0ubuntu1~ubuntu16.04.1",
        "2.0.5-0ubuntu1~ubuntu16.04.1",
        "2.0.8-0ubuntu1~ubuntu16.04.1",
        "2.0.8-0ubuntu1~ubuntu16.04.2",
        "2.0.9-0ubuntu1~16.04.1",
        "2.0.9-0ubuntu1~16.04.2",
        "2.0.10-0ubuntu1~16.04.1",
        "2.0.10-0ubuntu1~16.04.2",
        "2.0.11-0ubuntu1~16.04.2",
        "2.0.11-0ubuntu1~16.04.4",
        "2.0.11-0ubuntu1~16.04.4+esm1",
        "2.0.11-0ubuntu1~16.04.4+esm2",
        "2.0.11-0ubuntu1~16.04.4+esm3"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "lxd",
            "binary_version": "3.0.3-0ubuntu1~18.04.2+esm3"
          },
          {
            "binary_name": "lxd-client",
            "binary_version": "3.0.3-0ubuntu1~18.04.2+esm3"
          },
          {
            "binary_name": "lxd-tools",
            "binary_version": "3.0.3-0ubuntu1~18.04.2+esm3"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:Pro:18.04:LTS",
        "name": "lxd",
        "purl": "pkg:deb/ubuntu/lxd@3.0.3-0ubuntu1~18.04.2+esm3?arch=source\u0026distro=esm-infra/bionic"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "2.18-0ubuntu6",
        "2.19-0ubuntu1",
        "2.20-0ubuntu3",
        "2.20-0ubuntu4",
        "2.21-0ubuntu1",
        "2.21-0ubuntu2",
        "2.21-0ubuntu3",
        "2.21-0ubuntu4",
        "3.0.0~beta2-0ubuntu3",
        "3.0.0~beta3-0ubuntu3",
        "3.0.0~beta5-0ubuntu2",
        "3.0.0~beta7-0ubuntu1",
        "3.0.0-0ubuntu1",
        "3.0.0-0ubuntu2",
        "3.0.0-0ubuntu3",
        "3.0.0-0ubuntu4",
        "3.0.1-0ubuntu1~18.04.1",
        "3.0.2-0ubuntu1~18.04.1",
        "3.0.3-0ubuntu1~18.04.1",
        "3.0.3-0ubuntu1~18.04.2",
        "3.0.3-0ubuntu1~18.04.2+esm1",
        "3.0.3-0ubuntu1~18.04.2+esm2",
        "3.0.3-0ubuntu1~18.04.2+esm3"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "lxd",
            "binary_version": "1:0.10"
          },
          {
            "binary_name": "lxd-client",
            "binary_version": "1:0.10"
          },
          {
            "binary_name": "lxd-tools",
            "binary_version": "1:0.10"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:20.04:LTS",
        "name": "lxd",
        "purl": "pkg:deb/ubuntu/lxd@1:0.10?arch=source\u0026distro=focal"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "1:0.7",
        "1:0.8",
        "1:0.9",
        "1:0.10"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "golang-github-lxc-incus-dev",
            "binary_version": "6.0.0-1ubuntu0.3+esm3"
          },
          {
            "binary_name": "incus",
            "binary_version": "6.0.0-1ubuntu0.3+esm3"
          },
          {
            "binary_name": "incus-agent",
            "binary_version": "6.0.0-1ubuntu0.3+esm3"
          },
          {
            "binary_name": "incus-client",
            "binary_version": "6.0.0-1ubuntu0.3+esm3"
          },
          {
            "binary_name": "incus-migrate",
            "binary_version": "6.0.0-1ubuntu0.3+esm3"
          },
          {
            "binary_name": "incus-tools",
            "binary_version": "6.0.0-1ubuntu0.3+esm3"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:Pro:24.04:LTS",
        "name": "incus",
        "purl": "pkg:deb/ubuntu/incus@6.0.0-1ubuntu0.3+esm3?arch=source\u0026distro=esm-apps/noble"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "0.4-1ubuntu1",
        "0.5.1-1",
        "0.5.1-3",
        "0.6-1",
        "6.0.0-1",
        "6.0.0-1ubuntu0.1",
        "6.0.0-1ubuntu0.2",
        "6.0.0-1ubuntu0.2+esm1",
        "6.0.0-1ubuntu0.3",
        "6.0.0-1ubuntu0.3+esm1",
        "6.0.0-1ubuntu0.3+esm2",
        "6.0.0-1ubuntu0.3+esm3"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "golang-github-lxc-incus-dev",
            "binary_version": "6.0.4-2"
          },
          {
            "binary_name": "incus",
            "binary_version": "6.0.4-2"
          },
          {
            "binary_name": "incus-agent",
            "binary_version": "6.0.4-2"
          },
          {
            "binary_name": "incus-base",
            "binary_version": "6.0.4-2"
          },
          {
            "binary_name": "incus-client",
            "binary_version": "6.0.4-2"
          },
          {
            "binary_name": "incus-extra",
            "binary_version": "6.0.4-2"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:25.10",
        "name": "incus",
        "purl": "pkg:deb/ubuntu/incus@6.0.4-2?arch=source\u0026distro=questing"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "6.0.3-4",
        "6.0.4-2"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "golang-github-lxc-incus-dev",
            "binary_version": "6.0.5-8ubuntu0.26.04.1~esm1"
          },
          {
            "binary_name": "incus",
            "binary_version": "6.0.5-8ubuntu0.26.04.1~esm1"
          },
          {
            "binary_name": "incus-agent",
            "binary_version": "6.0.5-8ubuntu0.26.04.1~esm1"
          },
          {
            "binary_name": "incus-base",
            "binary_version": "6.0.5-8ubuntu0.26.04.1~esm1"
          },
          {
            "binary_name": "incus-client",
            "binary_version": "6.0.5-8ubuntu0.26.04.1~esm1"
          },
          {
            "binary_name": "incus-extra",
            "binary_version": "6.0.5-8ubuntu0.26.04.1~esm1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:Pro:26.04:LTS",
        "name": "incus",
        "purl": "pkg:deb/ubuntu/incus@6.0.5-8ubuntu0.26.04.1~esm1?arch=source\u0026distro=esm-apps/resolute"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "6.0.4-2",
        "6.0.5-8",
        "6.0.5-8ubuntu0.26.04.1~esm1"
      ]
    }
  ],
  "aliases": [],
  "details": "Incus is a system container and virtual machine manager. Prior to version 7.1.0, `(*backend).CreateCustomVolumeFromBackup` in `internal/server/storage/backend.go` contains an unguarded `*time.Time` dereference on the `ExpiresAt` field of every volume-snapshot entry in an imported custom-volume backup. An authenticated user with `can_create_storage_volumes` permission on any project can crash the `incusd` daemon by uploading a backup tarball whose `volume_snapshots[*].expires_at` field is absent. This is a sibling-field variant of GHSA-r7w7-mmxr-47r9 (CVE-2026-40197). Commit `985a1dedf9f3e7ba729c93b654905ed510de25c2` added `if s == nil` at the top of the loop body, but did not guard the adjacent `*snapshot.ExpiresAt` deref 19 lines later. Every other consumer of `Config.VolumeSnapshots[i].ExpiresAt` in this same file already gates the deref with a nil-check \u2014 the asymmetric guard is the bug. Version 7.1.0 contains an updated patch.",
  "id": "UBUNTU-CVE-2026-48756",
  "modified": "2026-09-02T16:18:21Z",
  "published": "2026-08-21T15:16:00Z",
  "references": [
    {
      "type": "REPORT",
      "url": "https://ubuntu.com/security/CVE-2026-48756"
    },
    {
      "type": "REPORT",
      "url": "https://www.cve.org/CVERecord?id=CVE-2026-48756"
    },
    {
      "type": "REPORT",
      "url": "https://github.com/lxc/incus/pull/3425"
    },
    {
      "type": "REPORT",
      "url": "https://github.com/lxc/incus/security/advisories/GHSA-xhqx-mgh3-3h7q"
    }
  ],
  "related": [],
  "schema_version": "1.7.0",
  "severity": [
    {
      "score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:P",
      "type": "CVSS_V4"
    },
    {
      "score": "medium",
      "type": "Ubuntu"
    }
  ],
  "upstream": [
    "CVE-2026-48756"
  ]
}

CVE-2026-48756 (GCVE-0-2026-48756)

Vulnerability from cvelistv5 – Published: 2026-08-21 14:10 – Updated: 2026-08-21 21:44

Title

Incus: CreateCustomVolumeFromBackup nil-pointer dereference on volume_snapshots[*].expires_at (sibling-field variant of GHSA-r7w7)

Summary

Incus is a system container and virtual machine manager. Prior to version 7.1.0, `(*backend).CreateCustomVolumeFromBackup` in `internal/server/storage/backend.go` contains an unguarded `*time.Time` dereference on the `ExpiresAt` field of every volume-snapshot entry in an imported custom-volume backup. An authenticated user with `can_create_storage_volumes` permission on any project can crash the `incusd` daemon by uploading a backup tarball whose `volume_snapshots[*].expires_at` field is absent. This is a sibling-field variant of GHSA-r7w7-mmxr-47r9 (CVE-2026-40197). Commit `985a1dedf9f3e7ba729c93b654905ed510de25c2` added `if s == nil` at the top of the loop body, but did not guard the adjacent `*snapshot.ExpiresAt` deref 19 lines later. Every other consumer of `Config.VolumeSnapshots[i].ExpiresAt` in this same file already gates the deref with a nil-check — the asymmetric guard is the bug. Version 7.1.0 contains an updated patch.

Severity

2.1 (Low)


                        
                          CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:P

SSVC

Exploitation: none Automatable: no Technical Impact: partial

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-08-21 20:58 UTC

CWE

CWE-476 - NULL Pointer Dereference

Assigner

GitHub_M mitre root

References

1 reference

URL	Tags
https://github.com/lxc/incus/security/advisories/…	x_refsource_CONFIRM

Impacted products

1 product

Vendor	Product	Version
lxc	incus	Affected: < 7.1.0

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2026-48756",
                "options": [
                  {
                    "Exploitation": "none"
                  },
                  {
                    "Automatable": "no"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-08-21T20:58:24.750230Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2026-08-21T21:44:23.844Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
          "product": "incus",
          "vendor": "lxc",
          "versions": [
            {
              "status": "affected",
              "version": "\u003c 7.1.0"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "Incus is a system container and virtual machine manager. Prior to version 7.1.0, `(*backend).CreateCustomVolumeFromBackup` in `internal/server/storage/backend.go` contains an unguarded `*time.Time` dereference on the `ExpiresAt` field of every volume-snapshot entry in an imported custom-volume backup. An authenticated user with `can_create_storage_volumes` permission on any project can crash the `incusd` daemon by uploading a backup tarball whose `volume_snapshots[*].expires_at` field is absent. This is a sibling-field variant of GHSA-r7w7-mmxr-47r9 (CVE-2026-40197). Commit `985a1dedf9f3e7ba729c93b654905ed510de25c2` added `if s == nil` at the top of the loop body, but did not guard the adjacent `*snapshot.ExpiresAt` deref 19 lines later. Every other consumer of `Config.VolumeSnapshots[i].ExpiresAt` in this same file already gates the deref with a nil-check \u2014 the asymmetric guard is the bug. Version 7.1.0 contains an updated patch."
        }
      ],
      "metrics": [
        {
          "cvssV4_0": {
            "attackComplexity": "LOW",
            "attackRequirements": "NONE",
            "attackVector": "NETWORK",
            "baseScore": 2.1,
            "baseSeverity": "LOW",
            "privilegesRequired": "LOW",
            "subAvailabilityImpact": "NONE",
            "subConfidentialityImpact": "NONE",
            "subIntegrityImpact": "NONE",
            "userInteraction": "NONE",
            "vectorString": "CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:P",
            "version": "4.0",
            "vulnAvailabilityImpact": "LOW",
            "vulnConfidentialityImpact": "NONE",
            "vulnIntegrityImpact": "NONE"
          }
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-476",
              "description": "CWE-476: NULL Pointer Dereference",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-08-21T14:10:34.151Z",
        "orgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
        "shortName": "GitHub_M"
      },
      "references": [
        {
          "name": "https://github.com/lxc/incus/security/advisories/GHSA-xhqx-mgh3-3h7q",
          "tags": [
            "x_refsource_CONFIRM"
          ],
          "url": "https://github.com/lxc/incus/security/advisories/GHSA-xhqx-mgh3-3h7q"
        }
      ],
      "source": {
        "advisory": "GHSA-xhqx-mgh3-3h7q",
        "discovery": "UNKNOWN"
      },
      "title": "Incus: CreateCustomVolumeFromBackup nil-pointer dereference on volume_snapshots[*].expires_at (sibling-field variant of GHSA-r7w7)"
    }
  },
  "cveMetadata": {
    "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
    "assignerShortName": "GitHub_M",
    "cveId": "CVE-2026-48756",
    "datePublished": "2026-08-21T14:10:34.151Z",
    "dateReserved": "2026-05-22T19:39:05.356Z",
    "dateUpdated": "2026-08-21T21:44:23.844Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}

Sightings

Author	Source	Type	Date	Other

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

Detection rules are retrieved from Rulezet.

The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.