CVE-2020-5256
Estado: ModificadaAlta (8.8)—
BookStack before version 0.25.5 has a vulnerability where a user could upload PHP files through image upload functions, which would allow them to execute code on the host system remotely. They would then have the permissions of the PHP process. This most impacts scenarios where non-trusted users are given permission to upload images in any area of the application. The issue was addressed in a series of patches in versions 0.25.3, 0.25.4 and 0.25.5. Users should upgrade to at least v0.25.5 to avoid this vulnerability.
CVSS
- Versión: 3.1
- Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
- Puntuación base: 8.8
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-95
- CWE-434
Referencias
- https://github.com/BookStackApp/BookStack/releases/tag/v0.25.3
- https://github.com/BookStackApp/BookStack/releases/tag/v0.25.4
- https://github.com/BookStackApp/BookStack/releases/tag/v0.25.5
- https://github.com/BookStackApp/BookStack/security/advisories/GHSA-g9rq-x4fj-f5hx
- https://github.com/BookStackApp/BookStack/releases/tag/v0.25.3
- https://github.com/BookStackApp/BookStack/releases/tag/v0.25.4
- https://github.com/BookStackApp/BookStack/releases/tag/v0.25.5
- https://github.com/BookStackApp/BookStack/security/advisories/GHSA-g9rq-x4fj-f5hx
JSON original (NVD)
Mostrar
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