Vulnerability-Lookup

CVE-2026-90616 (GCVE-0-2026-90616)

Vulnerability from cvelistv5 – Published: 2026-09-12 20:00 – Updated: 2026-09-12 20:00

Summary

In Flatpak before 1.18.1, a malicious sandboxed app can obtain arbitrary read and write access to files on the host, which can be escalated to arbitrary code execution on the host, a different vulnerability than CVE-2026-76925. Flatpak creates a few app data directories (e.g., /var/cache, /var/data, /var/config, and /var/tmp) in every sandbox on every app launch where, in some cases, components of the path are attacker-controlled. Missing symlink protection can redirect the directories. Some of these directories are bind-mounted by Flatpak by passing the path (e.g., /home/user/.var/app/APP_ID/cache/tmp), which contains attacker-controlled directories (tmp) to bwrap --bind SRC DST. bwrap passes the path on to the kernel, which then follows symlinks. A malicious symlink can point to arbitrary locations on the host and it will become mounted inside the sandbox.

Severity

7.4 (High)


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

CWE

CWE-61 - UNIX Symbolic Link (Symlink) Following

Assigner

mitre mitre root

References

2 references

URL	Tags
https://github.com/flatpak/flatpak/security/advis…
https://www.openwall.com/lists/oss-security/2026/…

Impacted products

1 product

Vendor	Product	Version	CPE status
Flatpak	Flatpak	Affected: 0 , < 1.18.1 (semver) cpe:2.3:a:flatpak:flatpak::::::::

Show details on NVD website

JSON

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{
  "containers": {
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "platforms": [
            "Linux"
          ],
          "product": "Flatpak",
          "repo": "https://github.com/flatpak/flatpak",
          "vendor": "Flatpak",
          "versions": [
            {
              "lessThan": "1.18.1",
              "status": "affected",
              "version": "0",
              "versionType": "semver"
            }
          ]
        }
      ],
      "cpeApplicability": [
        {
          "nodes": [
            {
              "cpeMatch": [
                {
                  "criteria": "cpe:2.3:a:flatpak:flatpak:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "1.18.1",
                  "vulnerable": true
                }
              ],
              "negate": false,
              "operator": "OR"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "In Flatpak before 1.18.1, a malicious sandboxed app can obtain arbitrary read and write access to files on the host, which can be escalated to arbitrary code execution on the host, a different vulnerability than CVE-2026-76925. Flatpak creates a few app data directories (e.g., /var/cache, /var/data, /var/config, and /var/tmp) in every sandbox on every app launch where, in some cases, components of the path are attacker-controlled. Missing symlink protection can redirect the directories. Some of these directories are bind-mounted by Flatpak by passing the path (e.g., /home/user/.var/app/APP_ID/cache/tmp), which contains attacker-controlled directories (tmp) to bwrap --bind SRC DST. bwrap passes the path on to the kernel, which then follows symlinks. A malicious symlink can point to arbitrary locations on the host and it will become mounted inside the sandbox."
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "attackComplexity": "HIGH",
            "attackVector": "LOCAL",
            "availabilityImpact": "HIGH",
            "baseScore": 7.4,
            "baseSeverity": "HIGH",
            "confidentialityImpact": "HIGH",
            "integrityImpact": "HIGH",
            "privilegesRequired": "NONE",
            "scope": "UNCHANGED",
            "userInteraction": "NONE",
            "vectorString": "CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H",
            "version": "3.1"
          },
          "format": "CVSS",
          "scenarios": [
            {
              "lang": "en",
              "value": "GENERAL"
            }
          ]
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-61",
              "description": "CWE-61 UNIX Symbolic Link (Symlink) Following",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-09-12T20:00:58.476Z",
        "orgId": "8254265b-2729-46b6-b9e3-3dfca2d5bfca",
        "shortName": "mitre"
      },
      "references": [
        {
          "url": "https://github.com/flatpak/flatpak/security/advisories/GHSA-8688-9x26-hhxj"
        },
        {
          "url": "https://www.openwall.com/lists/oss-security/2026/08/11/9"
        }
      ],
      "solutions": [
        {
          "lang": "en",
          "supportingMedia": [
            {
              "base64": false,
              "type": "text/html",
              "value": "\u003ca target=\"_blank\" rel=\"noopener noreferrer\" href=\"https://github.com/flatpak/flatpak/commit/478072972056d2d15c768c246f80abdf83cf0e5e\"\u003ehttps://github.com/flatpak/flatpak/commit/478072972056d2d15c768c246f80abdf83cf0e5e\u003c/a\u003e\u003cbr\u003e"
            }
          ],
          "value": "https://github.com/flatpak/flatpak/commit/478072972056d2d15c768c246f80abdf83cf0e5e"
        }
      ],
      "x_generator": {
        "engine": "CVE-Request-form 0.0.1"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "8254265b-2729-46b6-b9e3-3dfca2d5bfca",
    "assignerShortName": "mitre",
    "cveId": "CVE-2026-90616",
    "datePublished": "2026-09-12T20:00:58.476Z",
    "dateReserved": "2026-09-12T20:00:58.046Z",
    "dateUpdated": "2026-09-12T20:00:58.476Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2",
  "vulnerability-lookup:meta": {
    "nvd": "{\"cve\":{\"id\":\"CVE-2026-90616\",\"sourceIdentifier\":\"cve@mitre.org\",\"published\":\"2026-09-12T20:16:30.957\",\"lastModified\":\"2026-09-12T20:16:30.957\",\"vulnStatus\":\"Received\",\"cveTags\":[],\"descriptions\":[{\"lang\":\"en\",\"value\":\"In Flatpak before 1.18.1, a malicious sandboxed app can obtain arbitrary read and write access to files on the host, which can be escalated to arbitrary code execution on the host, a different vulnerability than CVE-2026-76925. Flatpak creates a few app data directories (e.g., /var/cache, /var/data, /var/config, and /var/tmp) in every sandbox on every app launch where, in some cases, components of the path are attacker-controlled. Missing symlink protection can redirect the directories. Some of these directories are bind-mounted by Flatpak by passing the path (e.g., /home/user/.var/app/APP_ID/cache/tmp), which contains attacker-controlled directories (tmp) to bwrap --bind SRC DST. bwrap passes the path on to the kernel, which then follows symlinks. A malicious symlink can point to arbitrary locations on the host and it will become mounted inside the sandbox.\"}],\"affected\":[{\"source\":\"cve@mitre.org\",\"affectedData\":[{\"vendor\":\"Flatpak\",\"product\":\"Flatpak\",\"defaultStatus\":\"unaffected\",\"platforms\":[\"Linux\"],\"repo\":\"https://github.com/flatpak/flatpak\",\"versions\":[{\"version\":\"0\",\"lessThan\":\"1.18.1\",\"versionType\":\"semver\",\"status\":\"affected\"}]}]}],\"metrics\":{\"cvssMetricV31\":[{\"source\":\"cve@mitre.org\",\"type\":\"Secondary\",\"cvssData\":{\"version\":\"3.1\",\"vectorString\":\"CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H\",\"baseScore\":7.4,\"baseSeverity\":\"HIGH\",\"attackVector\":\"LOCAL\",\"attackComplexity\":\"HIGH\",\"privilegesRequired\":\"NONE\",\"userInteraction\":\"NONE\",\"scope\":\"UNCHANGED\",\"confidentialityImpact\":\"HIGH\",\"integrityImpact\":\"HIGH\",\"availabilityImpact\":\"HIGH\"},\"exploitabilityScore\":1.4,\"impactScore\":5.9}]},\"weaknesses\":[{\"source\":\"cve@mitre.org\",\"type\":\"Primary\",\"description\":[{\"lang\":\"en\",\"value\":\"CWE-61\"}]}],\"references\":[{\"url\":\"https://github.com/flatpak/flatpak/security/advisories/GHSA-8688-9x26-hhxj\",\"source\":\"cve@mitre.org\"},{\"url\":\"https://www.openwall.com/lists/oss-security/2026/08/11/9\",\"source\":\"cve@mitre.org\"}]}}",
    "redhat_vex": {
      "aggregate_severity": "Important",
      "current_release_date": "2026-09-14T08:14:37+00:00",
      "cve": "CVE-2026-90616",
      "id": "CVE-2026-90616",
      "initial_release_date": "2026-09-12T20:00:58.476000+00:00",
      "product_status:known_affected": "23",
      "source": "Red Hat CSAF VEX",
      "status": "final",
      "title": "flatpak: Flatpak: Arbitrary code execution via missing symlink protection",
      "url": "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-90616.json",
      "version": "3"
    }
  }
}

FKIE_CVE-2026-90616

Vulnerability from fkie_nvd - Published: 2026-09-12 20:16 - Updated: 2026-09-12 20:16

Severity

7.4 (High) - CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H

Summary

References

	URL	Tags
	cve@mitre.org	https://github.com/flatpak/flatpak/security/advisories/GHSA-8688-9x26-hhxj
	cve@mitre.org	https://www.openwall.com/lists/oss-security/2026/08/11/9

Impacted products

	Vendor	Product	Version

JSON

To clipboard

{
  "affected": [
    {
      "affectedData": [
        {
          "defaultStatus": "unaffected",
          "platforms": [
            "Linux"
          ],
          "product": "Flatpak",
          "repo": "https://github.com/flatpak/flatpak",
          "vendor": "Flatpak",
          "versions": [
            {
              "lessThan": "1.18.1",
              "status": "affected",
              "version": "0",
              "versionType": "semver"
            }
          ]
        }
      ],
      "source": "cve@mitre.org"
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In Flatpak before 1.18.1, a malicious sandboxed app can obtain arbitrary read and write access to files on the host, which can be escalated to arbitrary code execution on the host, a different vulnerability than CVE-2026-76925. Flatpak creates a few app data directories (e.g., /var/cache, /var/data, /var/config, and /var/tmp) in every sandbox on every app launch where, in some cases, components of the path are attacker-controlled. Missing symlink protection can redirect the directories. Some of these directories are bind-mounted by Flatpak by passing the path (e.g., /home/user/.var/app/APP_ID/cache/tmp), which contains attacker-controlled directories (tmp) to bwrap --bind SRC DST. bwrap passes the path on to the kernel, which then follows symlinks. A malicious symlink can point to arbitrary locations on the host and it will become mounted inside the sandbox."
    }
  ],
  "id": "CVE-2026-90616",
  "lastModified": "2026-09-12T20:16:30.957",
  "metrics": {
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "HIGH",
          "attackVector": "LOCAL",
          "availabilityImpact": "HIGH",
          "baseScore": 7.4,
          "baseSeverity": "HIGH",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "HIGH",
          "privilegesRequired": "NONE",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H",
          "version": "3.1"
        },
        "exploitabilityScore": 1.4,
        "impactScore": 5.9,
        "source": "cve@mitre.org",
        "type": "Secondary"
      }
    ]
  },
  "published": "2026-09-12T20:16:30.957",
  "references": [
    {
      "source": "cve@mitre.org",
      "url": "https://github.com/flatpak/flatpak/security/advisories/GHSA-8688-9x26-hhxj"
    },
    {
      "source": "cve@mitre.org",
      "url": "https://www.openwall.com/lists/oss-security/2026/08/11/9"
    }
  ],
  "sourceIdentifier": "cve@mitre.org",
  "vulnStatus": "Received",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-61"
        }
      ],
      "source": "cve@mitre.org",
      "type": "Primary"
    }
  ]
}

GHSA-VHX5-8PFJ-7WRV

Vulnerability from github – Published: 2026-09-12 21:31 – Updated: 2026-09-12 21:31

Details

Severity

7.4 (High)


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

Show details on source website

JSON

To clipboard

{
  "affected": [],
  "aliases": [
    "CVE-2026-90616"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-61"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-09-12T20:16:30Z",
    "severity": "HIGH"
  },
  "details": "In Flatpak before 1.18.1, a malicious sandboxed app can obtain arbitrary read and write access to files on the host, which can be escalated to arbitrary code execution on the host, a different vulnerability than CVE-2026-76925. Flatpak creates a few app data directories (e.g., /var/cache, /var/data, /var/config, and /var/tmp) in every sandbox on every app launch where, in some cases, components of the path are attacker-controlled. Missing symlink protection can redirect the directories. Some of these directories are bind-mounted by Flatpak by passing the path (e.g., /home/user/.var/app/APP_ID/cache/tmp), which contains attacker-controlled directories (tmp) to bwrap --bind SRC DST. bwrap passes the path on to the kernel, which then follows symlinks. A malicious symlink can point to arbitrary locations on the host and it will become mounted inside the sandbox.",
  "id": "GHSA-vhx5-8pfj-7wrv",
  "modified": "2026-09-12T21:31:12Z",
  "published": "2026-09-12T21:31:12Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/flatpak/flatpak/security/advisories/GHSA-8688-9x26-hhxj"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-90616"
    },
    {
      "type": "WEB",
      "url": "https://www.openwall.com/lists/oss-security/2026/08/11/9"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H",
      "type": "CVSS_V3"
    }
  ]
}

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.

Action not permitted

CVE-2026-90616 (GCVE-0-2026-90616)

FKIE_CVE-2026-90616

GHSA-VHX5-8PFJ-7WRV

Tags

Sightings

Nomenclature