gix-submodule before 0.29.0 (gitoxide before 0.5.21, gix before 0.84.0) incorrectly validates the update field in .gitmodules, allowing attackers to bypass the CommandForbiddenInModulesConfiguration guard when a submodule has been initialized with only partial configuration in .git/config. An attacker can inject arbitrary shell commands via the update field in .gitmodules that will be executed when Submodule::update() is called on a previously-initialized submodule, enabling remote code execution.
{
"cna_assigner": "VulnCheck",
"cwe_ids": [
"CWE-77"
],
"osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/40xxx/CVE-2026-40034.json",
"unresolved_ranges": [
{
"extracted_events": [
{
"range": [
{
"fixed": "0.5.21"
}
],
"source": "AFFECTED_FIELD",
"strategy": "StandardRange"
}
]
}
]
}{
"extracted_events": [
{
"range": [
{
"introduced": "0"
},
{
"fixed": "0.29.0"
}
],
"source": "AFFECTED_FIELD",
"strategy": "StandardRange"
},
{
"range": [
{
"introduced": "0"
},
{
"fixed": "0.84.0"
}
],
"source": "AFFECTED_FIELD",
"strategy": "StandardRange"
},
{
"range": [
{
"fixed": "6a2e6a436f76c8bbf2487f9967413a51356667a0"
}
],
"source": "REFERENCES_COMMIT"
},
{
"range": [
{
"fixed": "dd5c18d9e526e8de462fa40aa047acd097cfa7dc"
}
],
"source": "REFERENCES_COMMIT"
}
]
}