OESA-2026-2693 (CVE-2026-6231)
Vulnerability from osv_openeuler – Published: 2026-06-24 11:11 – Updated: 2026-08-06 11:11 – Source websitemongo-c-driver is a project that includes two libraries: libmongoc, a client library written in C for MongoDB. libbson, a library providing useful routines related to building, parsing, and iterating BSON documents.
Security Fix(es):
The bson_validate function may return early on specific inputs and incorrectly report success. This behavior could result in skipping validation for BSON data, allowing malformed or invalid UTF-8 sequences to bypass validation and be processed incorrectly. The issue may affect applications that rely on these functions to validate untrusted BSON data before further processing. This issue affects MongoDB C Driver versions prior to 1.30.5, MongoDB C Driver version 2.0.0 and MongoDB C Driver version 2.0.1.(CVE-2026-6231)
The MongoDB C Driver's Cyrus SASL integration performs unsafe string copying during username canonicalization, enabling a heap buffer overflow before any authentication or network traffic. This may be triggered by passing untrusted input in the username of a MongoDB URI with authMechanism=GSSAPI.(CVE-2026-6691)
| URL | Type | |
|---|---|---|
{
"affected": [
{
"ecosystem_specific": {
"aarch64": [
"libbson-1.27.4-3.oe2003sp4.aarch64.rpm",
"libbson-devel-1.27.4-3.oe2003sp4.aarch64.rpm",
"mongo-c-driver-1.27.4-3.oe2003sp4.aarch64.rpm",
"mongo-c-driver-debuginfo-1.27.4-3.oe2003sp4.aarch64.rpm",
"mongo-c-driver-debugsource-1.27.4-3.oe2003sp4.aarch64.rpm",
"mongo-c-driver-devel-1.27.4-3.oe2003sp4.aarch64.rpm",
"mongo-c-driver-help-1.27.4-3.oe2003sp4.aarch64.rpm"
],
"src": [
"mongo-c-driver-1.27.4-3.oe2003sp4.src.rpm"
],
"x86_64": [
"libbson-1.27.4-3.oe2003sp4.x86_64.rpm",
"libbson-devel-1.27.4-3.oe2003sp4.x86_64.rpm",
"mongo-c-driver-1.27.4-3.oe2003sp4.x86_64.rpm",
"mongo-c-driver-debuginfo-1.27.4-3.oe2003sp4.x86_64.rpm",
"mongo-c-driver-debugsource-1.27.4-3.oe2003sp4.x86_64.rpm",
"mongo-c-driver-devel-1.27.4-3.oe2003sp4.x86_64.rpm",
"mongo-c-driver-help-1.27.4-3.oe2003sp4.x86_64.rpm"
]
},
"package": {
"ecosystem": "openEuler:20.03-LTS-SP4",
"name": "mongo-c-driver",
"purl": "pkg:rpm/openEuler/mongo-c-driver\u0026distro=openEuler-20.03-LTS-SP4"
},
"ranges": [
{
"events": [
{
"introduced": "0"
},
{
"fixed": "1.27.4-3.oe2003sp4"
}
],
"type": "ECOSYSTEM"
}
]
}
],
"database_specific": {
"severity": "High"
},
"details": "mongo-c-driver is a project that includes two libraries: libmongoc, a client library written in C for MongoDB. libbson, a library providing useful routines related to building, parsing, and iterating BSON documents.\r\n\r\nSecurity Fix(es):\n\nThe bson_validate function may return early on specific inputs and incorrectly report success. This behavior could result in skipping validation for BSON data, allowing malformed or invalid UTF-8 sequences to bypass validation and be processed incorrectly. The issue may affect applications that rely on these functions to validate untrusted BSON data before further processing. This issue affects MongoDB C Driver versions prior to 1.30.5, MongoDB C Driver version 2.0.0 and MongoDB C Driver version 2.0.1.(CVE-2026-6231)\n\nThe MongoDB C Driver\u0026apos;s Cyrus SASL integration performs unsafe string copying during username canonicalization, enabling a heap buffer overflow before any authentication or network traffic. This may be triggered by passing untrusted input in the username of a MongoDB URI with authMechanism=GSSAPI.(CVE-2026-6691)",
"id": "OESA-2026-2693",
"modified": "2026-08-06T11:11:37Z",
"published": "2026-06-24T11:11:37Z",
"references": [
{
"type": "ADVISORY",
"url": "https://www.openeuler.org/zh/security/security-bulletins/detail/?id=openEuler-SA-2026-2693"
},
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2026-6231"
},
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2026-6691"
}
],
"schema_version": "1.7.2",
"severity": [
{
"score": "CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X",
"type": "CVSS_V4"
}
],
"summary": "mongo-c-driver security update",
"upstream": [
"CVE-2026-6231",
"CVE-2026-6691"
]
}
Sightings
| Author | Source | Type | Date | Other |
|---|
Nomenclature
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