Vulnerability-Lookup

UBUNTU-CVE-2026-96276 (CVE-2026-96276)

Vulnerability from osv_ubuntu – Published: 2026-09-23 00:00 – Updated: 2026-09-23 00:00 – Source website

Details

security update

Severity

N/A (UNKNOWN)


                    
                      medium

References

URL

Type

	https://ubuntu.com/security/CVE-2026-96276	REPORT
	https://www.cve.org/CVERecord?id=CVE-2026-96276	REPORT
	https://github.com/flatpak/flatpak/security/advis…	REPORT

JSON

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{
  "affected": [
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "flatpak",
            "binary_version": "1.0.9-0ubuntu0.4+esm1"
          },
          {
            "binary_name": "flatpak-tests",
            "binary_version": "1.0.9-0ubuntu0.4+esm1"
          },
          {
            "binary_name": "gir1.2-flatpak-1.0",
            "binary_version": "1.0.9-0ubuntu0.4+esm1"
          },
          {
            "binary_name": "libflatpak0",
            "binary_version": "1.0.9-0ubuntu0.4+esm1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:Pro:18.04:LTS",
        "name": "flatpak",
        "purl": "pkg:deb/ubuntu/flatpak@1.0.9-0ubuntu0.4+esm1?arch=source\u0026distro=esm-apps/bionic"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "0.8.7-5",
        "0.10.0-1",
        "0.10.0-2",
        "0.10.1-1",
        "0.10.2-1",
        "0.10.2.1-1",
        "0.10.2.1-2",
        "0.10.3-1",
        "0.11.1-0ubuntu1",
        "0.11.3-2",
        "0.11.3-3",
        "0.11.7-0ubuntu0.1",
        "1.0.1-0ubuntu0.1",
        "1.0.6-0ubuntu0.1",
        "1.0.7-0ubuntu0.18.04.1",
        "1.0.8-0ubuntu0.18.04.1",
        "1.0.9-0ubuntu0.1",
        "1.0.9-0ubuntu0.2",
        "1.0.9-0ubuntu0.3",
        "1.0.9-0ubuntu0.4",
        "1.0.9-0ubuntu0.4+esm1"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "flatpak",
            "binary_version": "1.6.5-0ubuntu0.5+esm1"
          },
          {
            "binary_name": "flatpak-tests",
            "binary_version": "1.6.5-0ubuntu0.5+esm1"
          },
          {
            "binary_name": "gir1.2-flatpak-1.0",
            "binary_version": "1.6.5-0ubuntu0.5+esm1"
          },
          {
            "binary_name": "libflatpak0",
            "binary_version": "1.6.5-0ubuntu0.5+esm1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:Pro:20.04:LTS",
        "name": "flatpak",
        "purl": "pkg:deb/ubuntu/flatpak@1.6.5-0ubuntu0.5+esm1?arch=source\u0026distro=esm-apps/focal"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "1.4.3-1",
        "1.6.0-1",
        "1.6.1-1",
        "1.6.2-1",
        "1.6.3-1",
        "1.6.5-0ubuntu0.1",
        "1.6.5-0ubuntu0.2",
        "1.6.5-0ubuntu0.3",
        "1.6.5-0ubuntu0.4",
        "1.6.5-0ubuntu0.5",
        "1.6.5-0ubuntu0.5+esm1"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "flatpak",
            "binary_version": "1.12.7-1ubuntu0.1+esm1"
          },
          {
            "binary_name": "flatpak-tests",
            "binary_version": "1.12.7-1ubuntu0.1+esm1"
          },
          {
            "binary_name": "gir1.2-flatpak-1.0",
            "binary_version": "1.12.7-1ubuntu0.1+esm1"
          },
          {
            "binary_name": "libflatpak0",
            "binary_version": "1.12.7-1ubuntu0.1+esm1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:Pro:22.04:LTS",
        "name": "flatpak",
        "purl": "pkg:deb/ubuntu/flatpak@1.12.7-1ubuntu0.1+esm1?arch=source\u0026distro=esm-apps/jammy"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "1.10.2-3",
        "1.12.2-1",
        "1.12.2-2",
        "1.12.3-1",
        "1.12.4-1",
        "1.12.5-1",
        "1.12.6-1",
        "1.12.7-1",
        "1.12.7-1ubuntu0.1",
        "1.12.7-1ubuntu0.1+esm1"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "flatpak",
            "binary_version": "1.14.6-1ubuntu0.1+esm1"
          },
          {
            "binary_name": "flatpak-tests",
            "binary_version": "1.14.6-1ubuntu0.1+esm1"
          },
          {
            "binary_name": "gir1.2-flatpak-1.0",
            "binary_version": "1.14.6-1ubuntu0.1+esm1"
          },
          {
            "binary_name": "libflatpak0",
            "binary_version": "1.14.6-1ubuntu0.1+esm1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:Pro:24.04:LTS",
        "name": "flatpak",
        "purl": "pkg:deb/ubuntu/flatpak@1.14.6-1ubuntu0.1+esm1?arch=source\u0026distro=esm-apps/noble"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "1.14.4-2",
        "1.14.5-1",
        "1.14.5-1build1",
        "1.14.5-1build4",
        "1.14.5-1build5",
        "1.14.5-1build6",
        "1.14.6-1",
        "1.14.6-1ubuntu0.1",
        "1.14.6-1ubuntu0.1+esm1"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "flatpak",
            "binary_version": "1.16.6-1"
          },
          {
            "binary_name": "flatpak-tests",
            "binary_version": "1.16.6-1"
          },
          {
            "binary_name": "gir1.2-flatpak-1.0",
            "binary_version": "1.16.6-1"
          },
          {
            "binary_name": "libflatpak0",
            "binary_version": "1.16.6-1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:26.04:LTS",
        "name": "flatpak",
        "purl": "pkg:deb/ubuntu/flatpak@1.16.6-1?arch=source\u0026distro=resolute"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "1.16.1-2ubuntu1",
        "1.16.1-3ubuntu1",
        "1.16.2-1",
        "1.16.3-1",
        "1.16.3-1build1",
        "1.16.4-1",
        "1.16.4-2",
        "1.16.6-1"
      ]
    }
  ],
  "aliases": [],
  "details": "security update",
  "id": "UBUNTU-CVE-2026-96276",
  "modified": "2026-09-23T00:00:00Z",
  "published": "2026-09-23T00:00:00Z",
  "references": [
    {
      "type": "REPORT",
      "url": "https://ubuntu.com/security/CVE-2026-96276"
    },
    {
      "type": "REPORT",
      "url": "https://www.cve.org/CVERecord?id=CVE-2026-96276"
    },
    {
      "type": "REPORT",
      "url": "https://github.com/flatpak/flatpak/security/advisories/GHSA-8qxj-x646-phcm"
    }
  ],
  "related": [],
  "schema_version": "1.7.0",
  "severity": [
    {
      "score": "medium",
      "type": "Ubuntu"
    }
  ],
  "upstream": [
    "CVE-2026-96276"
  ]
}

CVE-2026-96276 (GCVE-0-2026-96276)

Vulnerability from cvelistv5 – Published: 2026-09-23 15:01 – Updated: 2026-09-23 15:28

Title

Flatpak: flatpak: arbitrary write in host context via flatpak build-init

Summary

If a malicious SDK container declares an extension point with a crafted `directory` path, and a developer runs `flatpak build-init --writable-sdk --sdk-extension` with that SDK, attacker-chosen files could be written outside the working directory, since the target path is resolved via a function that allows `..` traversal.

Severity

9.8 (Critical)


                        
                          CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

SSVC

Exploitation: none Automatable: yes Technical Impact: total

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-09-23 15:28 UTC

CWE

CWE-22 - Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')

Assigner

redhat redhat root

References

3 references

URL	Tags
https://access.redhat.com/security/cve/CVE-2026-96276	vdb-entryx_refsource_REDHAT
https://bugzilla.redhat.com/show_bug.cgi?id=2539418	issue-trackingx_refsource_REDHAT
https://github.com/flatpak/flatpak/security/advis…

Impacted products

4 products

Vendor	Product	Version
Red Hat	Red Hat Enterprise Linux 10	cpe:/o:redhat:enterprise_linux:10
Red Hat	Red Hat Enterprise Linux 7	cpe:/o:redhat:enterprise_linux:7
Red Hat	Red Hat Enterprise Linux 8	cpe:/o:redhat:enterprise_linux:8
Red Hat	Red Hat Enterprise Linux 9	cpe:/o:redhat:enterprise_linux:9

Date Public

2026-08-11 00:00

Credits

Upstream acknowledges Sebastian Wick as the original reporter.

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "cvssV3_1": {
              "attackComplexity": "LOW",
              "attackVector": "NETWORK",
              "availabilityImpact": "HIGH",
              "baseScore": 9.8,
              "baseSeverity": "CRITICAL",
              "confidentialityImpact": "HIGH",
              "integrityImpact": "HIGH",
              "privilegesRequired": "NONE",
              "scope": "UNCHANGED",
              "userInteraction": "NONE",
              "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
              "version": "3.1"
            }
          },
          {
            "other": {
              "content": {
                "id": "CVE-2026-96276",
                "options": [
                  {
                    "Exploitation": "none"
                  },
                  {
                    "Automatable": "yes"
                  },
                  {
                    "Technical Impact": "total"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-09-23T15:28:10.393280Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2026-09-23T15:28:23.421Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
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          "collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
          "cpes": [
            "cpe:/o:redhat:enterprise_linux:10"
          ],
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          "packageName": "flatpak",
          "product": "Red Hat Enterprise Linux 10",
          "vendor": "Red Hat"
        },
        {
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          "cpes": [
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          "product": "Red Hat Enterprise Linux 7",
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        {
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          "cpes": [
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          "product": "Red Hat Enterprise Linux 8",
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        }
      ],
      "metrics": [
        {
          "other": {
            "content": {
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        },
        {
          "name": "RHBZ#2539418",
          "tags": [
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            "x_refsource_REDHAT"
          ],
          "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2539418"
        },
        {
          "url": "https://github.com/flatpak/flatpak/security/advisories/GHSA-8qxj-x646-phcm"
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      "timeline": [
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    "dateReserved": "2026-09-22T20:42:35.875Z",
    "dateUpdated": "2026-09-23T15:28:23.421Z",
    "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.

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.
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UBUNTU-CVE-2026-96276 (CVE-2026-96276)

CVE-2026-96276 (GCVE-0-2026-96276)

Tags

Sightings

Nomenclature

Related by attack behaviour