High
flatpak-builder — security advisory
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.
- Products
- flatpak-builder
- Affected versions
- 0.10.1-1, 0.10.4-1, 0.10.5-1, 0.10.6-1, 0.10.6-2, 0.10.7-1, 0.10.8-1, 0.10.9-1, 0.10.9-1ubuntu1, 1.0.10-1, 1.0.14-2, 1.0.8-2, 1.0.9-1, 1.2.0-1, 1.2.1-1, 1.2.2-1, 1.2.2-2, 1.2.3-1, 1.4.0-1, 1.4.1-1, 1.4.10-1, 1.4.11-1, 1.4.12-1, 1.4.2-1build1, 1.4.2-1build2, 1.4.6-2, 1.4.7-1, 1.4.8-1, 1.4.9-1
- Fixed versions
- Not specified
- CVEs
- CVE-2026-86320
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 31 Oct 2026, 03:24 UTC · Revision 1
Source evidence
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.
osv:UBUNTU-CVE-2026-86320
flatpak-builder
Fixed versions: Not specified
flatpak-builder
Fixed versions: Not specified
flatpak-builder
Fixed versions: Not specified
flatpak-builder
Fixed versions: Not specified
flatpak-builder
Fixed versions: Not specified
flatpak-builder
Fixed versions: Not specified
Complete source record
{
"id": "19c19596db8db81a59d4bfe8287bca8fb62021a995d425889af9413ffca2991f",
"url": "https://osv.dev/vulnerability/UBUNTU-CVE-2026-86320",
"method": "structured",
"payload": {
"kind": "advisory",
"title": "UBUNTU-CVE-2026-86320",
"summary": "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.",
"evidence": "osv:UBUNTU-CVE-2026-86320",
"products": [
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"evidence": "/affected/0/package/name"
},
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"affected_versions": [
{
"value": "0.10.1-1",
"evidence": "/affected/0/versions"
},
{
"value": "0.10.4-1",
"evidence": "/affected/0/versions"
},
{
"value": "0.10.5-1",
"evidence": "/affected/0/versions"
},
{
"value": "0.10.6-1",
"evidence": "/affected/0/versions"
},
{
"value": "0.10.6-2",
"evidence": "/affected/0/versions"
},
{
"value": "0.10.7-1",
"evidence": "/affected/0/versions"
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{
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"evidence": "/affected/0/versions"
},
{
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{
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{
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"evidence": "/affected/1/versions"
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{
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"evidence": "/affected/1/versions"
},
{
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}
]
},
{
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{
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"evidence": "/affected/2/versions"
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{
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"evidence": "/affected/2/versions"
},
{
"value": "1.2.1-1",
"evidence": "/affected/2/versions"
},
{
"value": "1.2.2-1",
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},
{
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},
{
"name": {
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},
"prerequisites": [],
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"affected_versions": [
{
"value": "1.2.3-1",
"evidence": "/affected/3/versions"
},
{
"value": "1.4.0-1",
"evidence": "/affected/3/versions"
},
{
"value": "1.4.1-1",
"evidence": "/affected/3/versions"
},
{
"value": "1.4.2-1build1",
"evidence": "/affected/3/versions"
},
{
"value": "1.4.2-1build2",
"evidence": "/affected/3/versions"
}
]
},
{
"name": {
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"evidence": "/affected/4/package/name"
},
"prerequisites": [],
"fixed_versions": [],
"affected_versions": [
{
"value": "1.4.8-1",
"evidence": "/affected/4/versions"
},
{
"value": "1.4.9-1",
"evidence": "/affected/4/versions"
},
{
"value": "1.4.10-1",
"evidence": "/affected/4/versions"
},
{
"value": "1.4.11-1",
"evidence": "/affected/4/versions"
},
{
"value": "1.4.12-1",
"evidence": "/affected/4/versions"
}
]
},
{
"name": {
"value": "flatpak-builder",
"evidence": "/affected/5/package/name"
},
"prerequisites": [],
"fixed_versions": [],
"affected_versions": [
{
"value": "1.4.6-2",
"evidence": "/affected/5/versions"
},
{
"value": "1.4.7-1",
"evidence": "/affected/5/versions"
},
{
"value": "1.4.8-1",
"evidence": "/affected/5/versions"
}
]
}
],
"severity": "high",
"structured": {
"id": "UBUNTU-CVE-2026-86320",
"aliases": [
"UBUNTU-CVE-2026-86320"
],
"metrics": [
{
"type": "CVSS_V3",
"score": "CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H"
},
{
"type": "Ubuntu",
"score": "medium"
}
],
"affected": [
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
}
]
}
],
"package": {
"name": "flatpak-builder",
"purl": "pkg:deb/ubuntu/flatpak-builder?arch=source&distro=bionic",
"ecosystem": "Ubuntu:18.04:LTS"
},
"versions": [
"0.10.1-1",
"0.10.4-1",
"0.10.5-1",
"0.10.6-1",
"0.10.6-2",
"0.10.7-1",
"0.10.8-1",
"0.10.9-1",
"0.10.9-1ubuntu1"
],
"database_specific": {
"source": "https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-86320.json"
},
"ecosystem_specific": {
"binaries": [
{
"binary_name": "flatpak-builder",
"binary_version": "0.10.9-1ubuntu1"
},
{
"binary_name": "flatpak-builder-tests",
"binary_version": "0.10.9-1ubuntu1"
}
]
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
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}
],
"package": {
"name": "flatpak-builder",
"purl": "pkg:deb/ubuntu/flatpak-builder?arch=source&distro=focal",
"ecosystem": "Ubuntu:20.04:LTS"
},
"versions": [
"1.0.8-2",
"1.0.9-1",
"1.0.10-1"
],
"database_specific": {
"source": "https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-86320.json"
},
"ecosystem_specific": {
"binaries": [
{
"binary_name": "flatpak-builder",
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},
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"binary_name": "flatpak-builder-tests",
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}
]
}
},
{
"ranges": [
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],
"package": {
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"purl": "pkg:deb/ubuntu/flatpak-builder?arch=source&distro=jammy",
"ecosystem": "Ubuntu:22.04:LTS"
},
"versions": [
"1.0.14-2",
"1.2.0-1",
"1.2.1-1",
"1.2.2-1",
"1.2.2-2"
],
"database_specific": {
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"ecosystem_specific": {
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"ecosystem": "Ubuntu:24.04:LTS"
},
"versions": [
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"1.4.0-1",
"1.4.1-1",
"1.4.2-1build1",
"1.4.2-1build2"
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},
"ecosystem_specific": {
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},
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"binary_name": "flatpak-builder-tests",
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}
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}
},
{
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"purl": "pkg:deb/ubuntu/flatpak-builder?arch=source&distro=stonking",
"ecosystem": "Ubuntu:26.10"
},
"versions": [
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"1.4.9-1",
"1.4.10-1",
"1.4.11-1",
"1.4.12-1"
],
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},
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"purl": "pkg:deb/ubuntu/flatpak-builder?arch=source&distro=resolute",
"ecosystem": "Ubuntu:26.04:LTS"
},
"versions": [
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"database_specific": {
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},
"ecosystem_specific": {
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}
],
"modified": "2026-10-17T13:01:13.617876Z",
"provider": "osv",
"upstream": [
"CVE-2026-86320"
],
"references": [
"https://ubuntu.com/security/CVE-2026-86320",
"https://www.cve.org/CVERecord?id=CVE-2026-86320",
"https://github.com/flatpak/flatpak-builder/security/advisories/GHSA-j5p8-jgjc-f3xv"
]
},
"related_cves": [
{
"value": "CVE-2026-86320",
"evidence": "/upstream"
}
],
"security_relevant": true,
"severity_evidence": "/severity/0/score"
},
"source_id": "core-osv",
"document_id": 361311,
"published_at": "2026-09-17T08:17:00+00:00"
}