CVE-2021-40353
A SQL injection vulnerability exists in version 8.0 of openSIS when MySQL or MariaDB is used as the application database. An attacker can then issue the SQL command through the index.php USERNAME parameter. NOTE: this issue may exist because of an incomplete fix for CVE-2020-6637.
CVSS
- Version: 3.1
- Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
- Base score: 9.8
Exploitation probability (EPSS)
- Probability of exploitation in the next 30 days: 2.88%
- Percentile among all scored CVEs: 86
- Score date: 10/7/2026
EPSS (Exploit Prediction Scoring System, FIRST) estimates how likely a vulnerability is to be exploited in the wild within 30 days. It complements CVSS (impact) and CISA KEV (confirmed exploitation).
💥 Public exploits
Exploit code or detection templates are publicly available. This is not the same as confirmed active exploitation (KEV), but it raises the risk: patch with priority.
- Proof of concept on GitHub (unverified) · List of proofs of concept on GitHub
⚠️ GitHub proofs of concept are not verified: some are fake or contain malware. Never run them outside an isolated lab.
Affected technologies (1)
CWEs
- CWE-89
References
Raw JSON (NVD)
Show
{
"id": "CVE-2021-40353",
"cveTags": [],
"metrics": {
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"vectorString": "AV:N/AC:L/Au:N/C:P/I:P/A:P",
"authentication": "NONE",
"integrityImpact": "PARTIAL",
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"affected": [
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"affectedData": [
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"published": "2021-09-01T01:15:07.027",
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"tags": [
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{
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"tags": [
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"description": [
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"descriptions": [
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"value": "A SQL injection vulnerability exists in version 8.0 of openSIS when MySQL or MariaDB is used as the application database. An attacker can then issue the SQL command through the index.php USERNAME parameter. NOTE: this issue may exist because of an incomplete fix for CVE-2020-6637."
},
{
"lang": "es",
"value": "Se presenta una vulnerabilidad de inyección SQL en la versión 8.0 de openSIS cuando MySQL o MariaDB es usado como base de datos de la aplicación. Un atacante puede emitir el comando SQL por medio del parámetro index.php USERNAME. NOTA: este problema puede existir debido a una solución incompleta para CVE-2020-6637"
}
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"lastModified": "2026-06-17T04:06:46.943",
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