CVE-2026-49131
OPNsense before 26.1.9 contains a stored cross-site scripting vulnerability that allows authenticated attackers with firewall rule management privileges to inject arbitrary HTML or JavaScript by embedding payloads in the firewall rule description field via the filter API endpoint. The unsanitized description value is persisted and later rendered through the default cell formatter in opnsense_bootgrid.js, which assigns raw cell content to innerHTML, causing injected scripts to execute in the browser of any authenticated user who views the Firewall Rules page, enabling session hijacking or credential theft.
CVSS
- Versión: 4.0
- Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:N/VI:N/VA:N/SC:L/SI:L/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
- Puntuación base: 5.1
Probabilidad de explotación (EPSS)
- Probabilidad de explotación en los próximos 30 días: 0.29%
- Percentil entre todas las CVEs puntuadas: 19
- Fecha de la puntuación: 5/10/2026
EPSS (Exploit Prediction Scoring System, de FIRST) estima la probabilidad de que una vulnerabilidad sea explotada en 30 días. Complementa a CVSS (impacto) y a CISA KEV (explotación confirmada).
Tecnologías afectadas (1)
⚠ Inferidas por IA a partir de la descripción — NVD aún no ha analizado esta CVE; no son CPE verificados.
CWE
- CWE-79
Referencias
JSON original (NVD)
Mostrar
{
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"version": "2.0.3",
"timestamp": "2026-08-04T14:00:38.957529Z"
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"vendor": "Deciso B.V.",
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"published": "2026-08-03T21:16:39.750",
"references": [
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"url": "https://docs.opnsense.org/releases/CE_26.1.html#june-02-2026",
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"url": "https://github.com/opnsense/core/commit/b11d6b340716e240868ab19a369e058a46f0876f",
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"description": [
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"value": "OPNsense before 26.1.9 contains a stored cross-site scripting vulnerability that allows authenticated attackers with firewall rule management privileges to inject arbitrary HTML or JavaScript by embedding payloads in the firewall rule description field via the filter API endpoint. The unsanitized description value is persisted and later rendered through the default cell formatter in opnsense_bootgrid.js, which assigns raw cell content to innerHTML, causing injected scripts to execute in the browser of any authenticated user who views the Firewall Rules page, enabling session hijacking or credential theft."
}
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"lastModified": "2026-09-16T20:32:21.400",
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