Firebird: Path Traversal + Arbitrary File Write Leads to Remote Code Execution
Firebird is an open-source relational database management system. In versions prior to 5.0.4, 4.0.7 and 3.0.14, the external engine plugin loader concatenates a user-supplied engine name into a filesystem path without filtering path separators or .. components. An authenticated user with CREATE FUNCTION privileges can use a crafted ENGINE name to load an arbitrary shared library from anywhere on the filesystem via path traversal. The library's initialization code executes immediately during loading, before Firebird validates the module, achieving code execution as the server's OS account. This issue has been fixed in versions 5.0.4, 4.0.7 and 3.0.14.
- Products
- Not specified
- Affected versions
- Not specified
- Fixed versions
- Not specified
- CVEs
- CVE-2026-40342
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 4 Nov 2026, 16:26 UTC · Revision 1
Source evidence
Firebird: Path Traversal + Arbitrary File Write Leads to Remote Code Execution
core-osv · Original sourcePublished 17 Apr 2026, 19:22 UTC
Firebird is an open-source relational database management system. In versions prior to 5.0.4, 4.0.7 and 3.0.14, the external engine plugin loader concatenates a user-supplied engine name into a filesystem path without filtering path separators or .. components. An authenticated user with CREATE FUNCTION privileges can use a crafted ENGINE name to load an arbitrary shared library from anywhere on the filesystem via path traversal. The library's initialization code executes immediately during loading, before Firebird validates the module, achieving code execution as the server's OS account. This issue has been fixed in versions 5.0.4, 4.0.7 and 3.0.14.
osv:CVE-2026-40342
Complete source record
{
"id": "932fd5aee831a3d0df41e58738e43d04ef14390f5c8514e8812555772569dd98",
"url": "https://osv.dev/vulnerability/CVE-2026-40342",
"method": "structured",
"payload": {
"kind": "advisory",
"title": "Firebird: Path Traversal + Arbitrary File Write Leads to Remote Code Execution",
"summary": "Firebird is an open-source relational database management system. In versions prior to 5.0.4, 4.0.7 and 3.0.14, the external engine plugin loader concatenates a user-supplied engine name into a filesystem path without filtering path separators or .. components. An authenticated user with CREATE FUNCTION privileges can use a crafted ENGINE name to load an arbitrary shared library from anywhere on the filesystem via path traversal. The library's initialization code executes immediately during loading, before Firebird validates the module, achieving code execution as the server's OS account. This issue has been fixed in versions 5.0.4, 4.0.7 and 3.0.14.",
"evidence": "osv:CVE-2026-40342",
"products": [],
"severity": "critical",
"structured": {
"id": "CVE-2026-40342",
"aliases": [
"CVE-2026-40342",
"GHSA-7pxc-h3rv-r257"
],
"metrics": [
{
"type": "CVSS_V3",
"score": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H"
}
],
"affected": [
{
"ranges": [
{
"repo": "https://github.com/firebirdsql/firebird",
"type": "GIT",
"events": [
{
"introduced": "0"
},
{
"fixed": "463bae029a4426deff7e9bb08a8317aaa398c7c7"
},
{
"introduced": "141bb5491d24cb363f03c5a0786a32f73a1faa5b"
},
{
"fixed": "26f6881c9eac77c5e3166d209682c0ebe8dd07c0"
},
{
"introduced": "af1546f15fa871b313ebcc7df1fd2df3c396c616"
},
{
"fixed": "f6d83a28c009ab039ea40ffdb4ccc58f190dfbe6"
}
],
"database_specific": {
"extracted_events": [
{
"cpe": "cpe:2.3:a:firebirdsql:firebird:*:*:*:*:*:*:*:*",
"range": [
{
"introduced": "0"
},
{
"fixed": "3.0.14"
}
],
"source": "CPE_RANGE"
},
{
"cpe": "cpe:2.3:a:firebirdsql:firebird:*:*:*:*:*:*:*:*",
"range": [
{
"introduced": "4.0.0"
},
{
"fixed": "4.0.7"
}
],
"source": "CPE_RANGE"
},
{
"cpe": "cpe:2.3:a:firebirdsql:firebird:*:*:*:*:*:*:*:*",
"range": [
{
"introduced": "5.0.0"
},
{
"fixed": "5.0.4"
}
],
"source": "CPE_RANGE"
},
{
"range": [
{
"fixed": "463bae029a4426deff7e9bb08a8317aaa398c7c7"
}
],
"source": "REFERENCES_TAG",
"original_tag": "v3.0.14"
},
{
"range": [
{
"fixed": "26f6881c9eac77c5e3166d209682c0ebe8dd07c0"
}
],
"source": "REFERENCES_TAG",
"original_tag": "v4.0.7"
},
{
"range": [
{
"fixed": "f6d83a28c009ab039ea40ffdb4ccc58f190dfbe6"
}
],
"source": "REFERENCES_TAG",
"original_tag": "v5.0.4"
}
]
}
}
],
"versions": [
"v3.0.13",
"v4.0.6",
"v5.0.3",
"v5.0.2",
"v3.0.12",
"v4.0.5",
"v5.0.1",
"v5.0.0",
"v4.0.4",
"v3.0.11",
"v4.0.3",
"v4.0.2",
"v3.0.10",
"v3.0.9",
"v4.0.1",
"v3.0.8",
"v4.0.0",
"R3_0_7",
"R3_0_6",
"R3_0_5",
"R3_0_4",
"R3_0_3",
"R3_0_2",
"R3_0_1",
"R3_0_0"
],
"database_specific": {
"source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-40342.json"
}
}
],
"modified": "2026-10-28T02:30:37.331752700Z",
"provider": "osv",
"references": [
"https://github.com/FirebirdSQL/firebird/releases/tag/v3.0.14",
"https://github.com/FirebirdSQL/firebird/releases/tag/v4.0.7",
"https://github.com/FirebirdSQL/firebird/releases/tag/v5.0.4",
"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/40xxx/CVE-2026-40342.json",
"https://github.com/FirebirdSQL/firebird/security/advisories/GHSA-7pxc-h3rv-r257",
"https://nvd.nist.gov/vuln/detail/CVE-2026-40342"
],
"provider_metadata": {
"cwe_ids": [
"CWE-22",
"CWE-427",
"CWE-73",
"CWE-94"
],
"cna_assigner": "GitHub_M",
"osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/40xxx/CVE-2026-40342.json"
}
},
"related_cves": [
{
"value": "CVE-2026-40342",
"evidence": "/id"
}
],
"security_relevant": true,
"severity_evidence": "/severity/0/score"
},
"source_id": "core-osv",
"document_id": 504623,
"published_at": "2026-04-17T19:22:46.644+00:00"
}