CVE-2026-26717
Estado: AplazadaMedia (4.8)—
An issue in OpenFUN Richie (LMS) in src/richie/apps/courses/api.py. The application used the non-constant time == operator for HMAC signature verification in the sync_course_run_from_request function. This allows remote attackers to forge valid signatures and bypass authentication by measuring response time discrepancies
CVSS
- Versión: 3.1
- Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N
- Puntuación base: 4.8
Probabilidad de explotación (EPSS)
- Probabilidad de explotación en los próximos 30 días: 0.51%
- Percentil entre todas las CVEs puntuadas: 41
- 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-208
Referencias
JSON original (NVD)
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{
"id": "CVE-2026-26717",
"cveTags": [],
"metrics": {
"ssvcV203": [
{
"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"ssvcData": {
"id": "CVE-2026-26717",
"role": "CISA Coordinator",
"options": [
{
"exploitation": "poc"
},
{
"automatable": "no"
},
{
"technicalImpact": "partial"
}
],
"version": "2.0.3",
"timestamp": "2026-02-26T19:10:20.591862Z"
}
}
],
"cvssMetricV31": [
{
"type": "Secondary",
"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"cvssData": {
"scope": "UNCHANGED",
"version": "3.1",
"baseScore": 4.8,
"attackVector": "NETWORK",
"baseSeverity": "MEDIUM",
"vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N",
"integrityImpact": "LOW",
"userInteraction": "NONE",
"attackComplexity": "HIGH",
"availabilityImpact": "NONE",
"privilegesRequired": "NONE",
"confidentialityImpact": "LOW"
},
"impactScore": 2.5,
"exploitabilityScore": 2.2
}
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"affected": [
{
"source": "cve@mitre.org",
"affectedData": [
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"vendor": "n/a",
"product": "n/a",
"versions": [
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],
"published": "2026-02-25T17:25:39.293",
"references": [
{
"url": "https://github.com/Rickidevs/CVE-2026-26717",
"source": "cve@mitre.org"
},
{
"url": "https://github.com/openfun/richie/commit/a1b5bbda3403d7debb466c303a32852925fcba5f",
"source": "cve@mitre.org"
},
{
"url": "https://medium.com/@ordogh/cve-2026-26717-hmac-timing-attack-in-openfun-richie-lms-f04377efe83d?postPublishedType=repub",
"source": "cve@mitre.org"
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"vulnStatus": "Deferred",
"weaknesses": [
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"description": [
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"descriptions": [
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"lang": "en",
"value": "An issue in OpenFUN Richie (LMS) in src/richie/apps/courses/api.py. The application used the non-constant time == operator for HMAC signature verification in the sync_course_run_from_request function. This allows remote attackers to forge valid signatures and bypass authentication by measuring response time discrepancies"
},
{
"lang": "es",
"value": "Un problema en OpenFUN Richie (LMS) en src/richie/apps/courses/api.py. La aplicación utilizó el operador == de tiempo no constante para la verificación de firmas HMAC en la función sync_course_run_from_request. Esto permite a atacantes remotos forjar firmas válidas y eludir la autenticación midiendo las discrepancias en el tiempo de respuesta."
}
],
"lastModified": "2026-06-17T10:26:15.757",
"sourceIdentifier": "cve@mitre.org"
}