CVE-2021-26236
Estado: ModificadaAlta (7.8)—
FastStone Image Viewer v.<= 7.5 is affected by a Stack-based Buffer Overflow at 0x005BDF49, affecting the CUR file parsing functionality (BITMAPINFOHEADER Structure, 'BitCount' file format field), that will end up corrupting the Structure Exception Handler (SEH). Attackers could exploit this issue to achieve code execution when a user opens or views a malformed/specially crafted CUR file.
CVSS
- Versión: 3.1
- Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
- Puntuación base: 7.8
Probabilidad de explotación (EPSS)
- Probabilidad de explotación en los próximos 30 días: 1.97%
- Percentil entre todas las CVEs puntuadas: 80
- Fecha de la puntuación: 6/10/2026
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)
CWE
- CWE-787
Referencias
- https://voidsec.com/advisories/cve-2021-26236-faststone-image-viewer-v-7-5-stack-based-buffer-overflow/
- https://voidsec.com/fuzzing-faststone-image-viewer-cve-2021-26236
- https://www.exploit-db.com/exploits/49660
- https://voidsec.com/advisories/cve-2021-26236-faststone-image-viewer-v-7-5-stack-based-buffer-overflow/
- https://voidsec.com/fuzzing-faststone-image-viewer-cve-2021-26236
- https://www.exploit-db.com/exploits/49660
JSON original (NVD)
Mostrar
{
"id": "CVE-2021-26236",
"cveTags": [],
"metrics": {
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{
"type": "Primary",
"source": "nvd@nist.gov",
"cvssData": {
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"baseScore": 6.8,
"accessVector": "NETWORK",
"vectorString": "AV:N/AC:M/Au:N/C:P/I:P/A:P",
"authentication": "NONE",
"integrityImpact": "PARTIAL",
"accessComplexity": "MEDIUM",
"availabilityImpact": "PARTIAL",
"confidentialityImpact": "PARTIAL"
},
"acInsufInfo": false,
"impactScore": 6.4,
"baseSeverity": "MEDIUM",
"obtainAllPrivilege": false,
"exploitabilityScore": 8.6,
"obtainUserPrivilege": false,
"obtainOtherPrivilege": false,
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}
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"cvssMetricV31": [
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"baseSeverity": "HIGH",
"vectorString": "CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H",
"integrityImpact": "HIGH",
"userInteraction": "REQUIRED",
"attackComplexity": "LOW",
"availabilityImpact": "HIGH",
"privilegesRequired": "NONE",
"confidentialityImpact": "HIGH"
},
"impactScore": 5.9,
"exploitabilityScore": 1.8
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"affected": [
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"source": "cve@mitre.org",
"affectedData": [
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"product": "n/a",
"versions": [
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}
],
"published": "2021-03-18T13:15:20.393",
"references": [
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"tags": [
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"source": "cve@mitre.org"
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{
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"tags": [
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"source": "af854a3a-2127-422b-91ae-364da2661108"
},
{
"url": "https://voidsec.com/fuzzing-faststone-image-viewer-cve-2021-26236",
"tags": [
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"tags": [
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"source": "af854a3a-2127-422b-91ae-364da2661108"
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],
"vulnStatus": "Modified",
"weaknesses": [
{
"type": "Primary",
"source": "nvd@nist.gov",
"description": [
{
"lang": "en",
"value": "CWE-787"
}
]
}
],
"descriptions": [
{
"lang": "en",
"value": "FastStone Image Viewer v.<= 7.5 is affected by a Stack-based Buffer Overflow at 0x005BDF49, affecting the CUR file parsing functionality (BITMAPINFOHEADER Structure, 'BitCount' file format field), that will end up corrupting the Structure Exception Handler (SEH). Attackers could exploit this issue to achieve code execution when a user opens or views a malformed/specially crafted CUR file."
},
{
"lang": "es",
"value": "FastStone Image Viewer versiones anteriores incluyendo a 7.5, está afectado por un desbordamiento del búfer en la región stack de la memoria en 0x005BDF49, que afecta la funcionalidad de análisis de archivos CUR (estructura BITMAPINFOHEADER, campo de formato de archivo \"BitCoun\"), que terminará corrompiendo el Structure Exception Handler (SEH) . Unos atacantes podrían explotar este problema para lograr una ejecución de código cuando un usuario abre o visualiza un archivo CUR malformado o especialmente diseñado"
}
],
"lastModified": "2026-06-17T03:42:59.830",
"configurations": [
{
"nodes": [
{
"negate": false,
"cpeMatch": [
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"criteria": "cpe:2.3:a:faststone:image_viewer:*:*:*:*:*:*:*:*",
"vulnerable": true,
"matchCriteriaId": "EF5DB16A-3B41-4691-8CE4-B8A98FA43CA2",
"versionEndIncluding": "7.5"
}
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"operator": "OR"
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],
"sourceIdentifier": "cve@mitre.org"
}