Vulnerability-Lookup

OESA-2026-4074 (CVE-2026-86320)

Vulnerability from osv_openeuler – Published: 2026-09-25 01:28 – Updated: 2026-09-25 01:28 – Source website

Summary

flatpak-builder security update

Details

Flatpak-builder is a tool for building flatpaks from sources.

Security Fix(es):

A flaw was found in flatpak-builder where Git hooks are not disabled when applying patch sources with use-git-am: true. An attacker who can provide a malicious source containing a Git post-applypatch hook can cause the hook to execute on the host during the build process, resulting in arbitrary code execution with the privileges of the user running flatpak-builder.(CVE-2026-86320)

Severity

7.8 (High)


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

References

URL

Type

	https://www.openeuler.org/zh/security/security-bu…	ADVISORY
	https://nvd.nist.gov/vuln/detail/CVE-2026-86320	ADVISORY

JSON

To clipboard

{
  "affected": [
    {
      "ecosystem_specific": {
        "aarch64": [
          "flatpak-builder-1.0.14-3.oe2203sp4.aarch64.rpm",
          "flatpak-builder-debuginfo-1.0.14-3.oe2203sp4.aarch64.rpm",
          "flatpak-builder-debugsource-1.0.14-3.oe2203sp4.aarch64.rpm"
        ],
        "src": [
          "flatpak-builder-1.0.14-3.oe2203sp4.src.rpm"
        ],
        "x86_64": [
          "flatpak-builder-1.0.14-3.oe2203sp4.x86_64.rpm",
          "flatpak-builder-debuginfo-1.0.14-3.oe2203sp4.x86_64.rpm",
          "flatpak-builder-debugsource-1.0.14-3.oe2203sp4.x86_64.rpm"
        ]
      },
      "package": {
        "ecosystem": "openEuler:22.03-LTS-SP4",
        "name": "flatpak-builder",
        "purl": "pkg:rpm/openEuler/flatpak-builder\u0026distro=openEuler-22.03-LTS-SP4"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "1.0.14-3.oe2203sp4"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "database_specific": {
    "severity": "High"
  },
  "details": "Flatpak-builder is a tool for building flatpaks from sources.\r\n\r\nSecurity Fix(es):\n\nA flaw was found in flatpak-builder where Git hooks are not disabled when applying patch sources with use-git-am: true. An attacker who can provide a malicious source containing a Git post-applypatch hook can cause the hook to execute on the host during the build process, resulting in arbitrary code execution with the privileges of the user running flatpak-builder.(CVE-2026-86320)",
  "id": "OESA-2026-4074",
  "modified": "2026-09-25T01:28:05Z",
  "published": "2026-09-25T01:28:05Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://www.openeuler.org/zh/security/security-bulletins/detail/?id=openEuler-SA-2026-4074"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-86320"
    }
  ],
  "schema_version": "1.7.2",
  "severity": [
    {
      "score": "CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H",
      "type": "CVSS_V3"
    }
  ],
  "summary": "flatpak-builder security update",
  "upstream": [
    "CVE-2026-86320"
  ]
}

CVE-2026-86320 (GCVE-0-2026-86320)

Vulnerability from cvelistv5 – Published: 2026-09-17 07:27 – Updated: 2026-09-17 15:54

Title

Flatpak-builder: host code execution via `git am` hook execution in patch source extraction (`use-git-am`)

Summary

Severity

7.8 (High)


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

SSVC

Exploitation: poc Automatable: no Technical Impact: total

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-09-17 15:42 UTC

CWE

CWE-94 - Improper Control of Generation of Code ('Code Injection')

Assigner

redhat redhat root

References

3 references

URL	Tags
https://access.redhat.com/security/cve/CVE-2026-86320	vdb-entryx_refsource_REDHAT
https://bugzilla.redhat.com/show_bug.cgi?id=2471023	issue-trackingx_refsource_REDHAT
https://github.com/flatpak/flatpak-builder/securi…

Impacted products

3 products

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

2026-08-13 14:32

Credits

Red Hat would like to thank AISLE Research for reporting this issue.

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2026-86320",
                "options": [
                  {
                    "Exploitation": "poc"
                  },
                  {
                    "Automatable": "no"
                  },
                  {
                    "Technical Impact": "total"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-09-17T15:42:59.014535Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2026-09-17T15:54:25.151Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "references": [
          {
            "tags": [
              "exploit"
            ],
            "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2471023"
          },
          {
            "tags": [
              "exploit"
            ],
            "url": "https://github.com/flatpak/flatpak-builder/security/advisories/GHSA-j5p8-jgjc-f3xv"
          }
        ],
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
          "collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
          "cpes": [
            "cpe:/o:redhat:enterprise_linux:10"
          ],
          "defaultStatus": "affected",
          "packageName": "flatpak-builder",
          "product": "Red Hat Enterprise Linux 10",
          "vendor": "Red Hat"
        },
        {
          "collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
          "cpes": [
            "cpe:/o:redhat:enterprise_linux:8"
          ],
          "defaultStatus": "affected",
          "packageName": "flatpak-builder",
          "product": "Red Hat Enterprise Linux 8",
          "vendor": "Red Hat"
        },
        {
          "collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
          "cpes": [
            "cpe:/o:redhat:enterprise_linux:9"
          ],
          "defaultStatus": "affected",
          "packageName": "flatpak-builder",
          "product": "Red Hat Enterprise Linux 9",
          "vendor": "Red Hat"
        }
      ],
      "credits": [
        {
          "lang": "en",
          "value": "Red Hat would like to thank AISLE Research for reporting this issue."
        }
      ],
      "datePublic": "2026-08-13T14:32:20.714Z",
      "descriptions": [
        {
          "lang": "en",
          "value": "A flaw was found in flatpak-builder where Git hooks are not disabled when applying patch sources with use-git-am: true. An attacker who can provide a malicious source containing a Git post-applypatch hook can cause the hook to execute on the host during the build process, resulting in arbitrary code execution with the privileges of the user running flatpak-builder."
        }
      ],
      "metrics": [
        {
          "other": {
            "content": {
              "namespace": "https://access.redhat.com/security/updates/classification/",
              "value": "Important"
            },
            "type": "Red Hat severity rating"
          }
        },
        {
          "cvssV3_1": {
            "attackComplexity": "LOW",
            "attackVector": "LOCAL",
            "availabilityImpact": "HIGH",
            "baseScore": 7.8,
            "baseSeverity": "HIGH",
            "confidentialityImpact": "HIGH",
            "integrityImpact": "HIGH",
            "privilegesRequired": "NONE",
            "scope": "UNCHANGED",
            "userInteraction": "REQUIRED",
            "vectorString": "CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H",
            "version": "3.1"
          },
          "format": "CVSS"
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-94",
              "description": "Improper Control of Generation of Code (\u0027Code Injection\u0027)",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-09-17T08:26:31.448Z",
        "orgId": "53f830b8-0a3f-465b-8143-3b8a9948e749",
        "shortName": "redhat"
      },
      "references": [
        {
          "tags": [
            "vdb-entry",
            "x_refsource_REDHAT"
          ],
          "url": "https://access.redhat.com/security/cve/CVE-2026-86320"
        },
        {
          "name": "RHBZ#2471023",
          "tags": [
            "issue-tracking",
            "x_refsource_REDHAT"
          ],
          "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2471023"
        },
        {
          "url": "https://github.com/flatpak/flatpak-builder/security/advisories/GHSA-j5p8-jgjc-f3xv"
        }
      ],
      "timeline": [
        {
          "lang": "en",
          "time": "2026-05-11T20:27:44.000Z",
          "value": "Reported to Red Hat."
        },
        {
          "lang": "en",
          "time": "2026-08-13T14:32:20.714Z",
          "value": "Made public."
        }
      ],
      "title": "Flatpak-builder: host code execution via `git am` hook execution in patch source extraction (`use-git-am`)",
      "workarounds": [
        {
          "lang": "en",
          "value": "Avoid using use-git-am: true when processing untrusted manifests or source material. Where untrusted builds are required, perform builds inside disposable virtual machines or other isolated environments."
        }
      ],
      "x_generator": {
        "engine": "cvelib 1.8.0"
      },
      "x_redhatCweChain": "CWE-94: Improper Control of Generation of Code (\u0027Code Injection\u0027)"
    }
  },
  "cveMetadata": {
    "assignerOrgId": "53f830b8-0a3f-465b-8143-3b8a9948e749",
    "assignerShortName": "redhat",
    "cveId": "CVE-2026-86320",
    "datePublished": "2026-09-17T07:27:33.167Z",
    "dateReserved": "2026-09-07T05:35:25.012Z",
    "dateUpdated": "2026-09-17T15:54:25.151Z",
    "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.
Browse all ATT&CK techniques and the vulnerabilities related to each.

Related by attack behaviour

Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.

Action not permitted

OESA-2026-4074 (CVE-2026-86320)

CVE-2026-86320 (GCVE-0-2026-86320)

Tags

Sightings

Nomenclature

Related by attack behaviour