OESA-2026-3936 (CVE-2026-9499)
Vulnerability from osv_openeuler – Published: 2026-09-20 13:23 – Updated: 2026-09-20 13:23 – Source websiteQt is a software toolkit for developing applications.
Security Fix(es):
An out-of-bounds read (buffer over-read) vulnerability exists in QTextCodec::codecForName() in Qt. When the function is called with a QByteArray that is not NUL-terminated (for example, one created with QByteArray::fromRawData()), the codec-name matching routine reads past the end of the supplied buffer. In most cases this results in an incorrect text codec being selected; in the worst case, if the over-read reaches unmapped memory, the process crashes (denial of service). The over-read is bounded by the length of the longest codec-name candidate, and the out-of-bounds bytes are only compared internally against Qt's fixed list of codec names, so no data is disclosed to an attacker. Applications that do not pass non-NUL-terminated QByteArrays to QTextCodec::codecForName() are not exposed. The affected code resides in the Qt5Compat module from Qt 6.0.0 onward, and in Qt Core (qtbase) in Qt 4.x and Qt 5.x.(CVE-2026-9499)
| URL | Type | |
|---|---|---|
{
"affected": [
{
"ecosystem_specific": {
"aarch64": [
"qt5-qtbase-5.15.10-17.oe2403sp3.aarch64.rpm",
"qt5-qtbase-debuginfo-5.15.10-17.oe2403sp3.aarch64.rpm",
"qt5-qtbase-debugsource-5.15.10-17.oe2403sp3.aarch64.rpm",
"qt5-qtbase-devel-5.15.10-17.oe2403sp3.aarch64.rpm",
"qt5-qtbase-examples-5.15.10-17.oe2403sp3.aarch64.rpm",
"qt5-qtbase-gui-5.15.10-17.oe2403sp3.aarch64.rpm",
"qt5-qtbase-mysql-5.15.10-17.oe2403sp3.aarch64.rpm",
"qt5-qtbase-odbc-5.15.10-17.oe2403sp3.aarch64.rpm",
"qt5-qtbase-postgresql-5.15.10-17.oe2403sp3.aarch64.rpm",
"qt5-qtbase-private-devel-5.15.10-17.oe2403sp3.aarch64.rpm",
"qt5-qtbase-static-5.15.10-17.oe2403sp3.aarch64.rpm"
],
"noarch": [
"qt5-qtbase-common-5.15.10-17.oe2403sp3.noarch.rpm"
],
"src": [
"qt5-qtbase-5.15.10-17.oe2403sp3.src.rpm"
],
"x86_64": [
"qt5-qtbase-5.15.10-17.oe2403sp3.x86_64.rpm",
"qt5-qtbase-debuginfo-5.15.10-17.oe2403sp3.x86_64.rpm",
"qt5-qtbase-debugsource-5.15.10-17.oe2403sp3.x86_64.rpm",
"qt5-qtbase-devel-5.15.10-17.oe2403sp3.x86_64.rpm",
"qt5-qtbase-examples-5.15.10-17.oe2403sp3.x86_64.rpm",
"qt5-qtbase-gui-5.15.10-17.oe2403sp3.x86_64.rpm",
"qt5-qtbase-mysql-5.15.10-17.oe2403sp3.x86_64.rpm",
"qt5-qtbase-odbc-5.15.10-17.oe2403sp3.x86_64.rpm",
"qt5-qtbase-postgresql-5.15.10-17.oe2403sp3.x86_64.rpm",
"qt5-qtbase-private-devel-5.15.10-17.oe2403sp3.x86_64.rpm",
"qt5-qtbase-static-5.15.10-17.oe2403sp3.x86_64.rpm"
]
},
"package": {
"ecosystem": "openEuler:24.03-LTS-SP3",
"name": "qt5-qtbase",
"purl": "pkg:rpm/openEuler/qt5-qtbase\u0026distro=openEuler-24.03-LTS-SP3"
},
"ranges": [
{
"events": [
{
"introduced": "0"
},
{
"fixed": "5.15.10-17.oe2403sp3"
}
],
"type": "ECOSYSTEM"
}
]
}
],
"database_specific": {
"severity": "Medium"
},
"details": "Qt is a software toolkit for developing applications.\r\n\r\nSecurity Fix(es):\n\nAn out-of-bounds read (buffer over-read) vulnerability exists in QTextCodec::codecForName() in Qt. When the function is called with a QByteArray that is not NUL-terminated (for example, one created with QByteArray::fromRawData()), the codec-name matching routine reads past the end of the supplied buffer. In most cases this results in an incorrect text codec being selected; in the worst case, if the over-read reaches unmapped memory, the process crashes (denial of service). The over-read is bounded by the length of the longest codec-name candidate, and the out-of-bounds bytes are only compared internally against Qt\u0026apos;s fixed list of codec names, so no data is disclosed to an attacker. Applications that do not pass non-NUL-terminated QByteArrays to QTextCodec::codecForName() are not exposed. The affected code resides in the Qt5Compat module from Qt 6.0.0 onward, and in Qt Core (qtbase) in Qt 4.x and Qt 5.x.(CVE-2026-9499)",
"id": "OESA-2026-3936",
"modified": "2026-09-20T13:23:23Z",
"published": "2026-09-20T13:23:23Z",
"references": [
{
"type": "ADVISORY",
"url": "https://www.openeuler.org/zh/security/security-bulletins/detail/?id=openEuler-SA-2026-3936"
},
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2026-9499"
}
],
"schema_version": "1.7.2",
"severity": [
{
"score": "CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:L/VA:L/SC:N/SI:N/SA:N",
"type": "CVSS_V4"
}
],
"summary": "qt5-qtbase security update",
"upstream": [
"CVE-2026-9499"
]
}
Sightings
| Author | Source | Type | Date | Other |
|---|
Nomenclature
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- 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.
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