CVE-2026-5484
A weakness has been identified in BookStackApp BookStack up to 26.03. Affected is the function chapterToMarkdown of the file app/Exports/ExportFormatter.php of the component Chapter Export Handler. Executing a manipulation of the argument pages can lead to improper access controls. It is possible to launch the attack remotely. The exploit has been made available to the public and could be used for attacks. Upgrading to version 26.03.1 is able to address this issue. This patch is called 8a59895ba063040cc8dafd82e94024c406df3d04. It is advisable to upgrade the affected component. The vendor was contacted early, responded in a very professional manner and quickly released a fixed version of the affected product.
CVSS
- Versión: 4.0
- Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N/E:P/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: 5.5
Probabilidad de explotación (EPSS)
- Probabilidad de explotación en los próximos 30 días: 0.55%
- Percentil entre todas las CVEs puntuadas: 44
- Fecha de la puntuación: 3/10/2026
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-266, CWE-284
Referencias
- https://github.com/BookStackApp/BookStack/
- https://github.com/BookStackApp/BookStack/commit/8a59895ba063040cc8dafd82e94024c406df3d04
- https://github.com/BookStackApp/BookStack/releases/tag/v26.03.1
- https://github.com/Ghufran2/CVE-Bookstack/blob/main/Permission%20Bypass%20in%20Markdown%20Chapter%20Export
- https://vuldb.com/submit/781762
- https://vuldb.com/vuln/355091
- https://vuldb.com/vuln/355091/cti
- https://www.bookstackapp.com/blog/bookstack-release-v26-03-1/
JSON original (NVD)
Mostrar
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"descriptions": [
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"lang": "en",
"value": "A weakness has been identified in BookStackApp BookStack up to 26.03. Affected is the function chapterToMarkdown of the file app/Exports/ExportFormatter.php of the component Chapter Export Handler. Executing a manipulation of the argument pages can lead to improper access controls. It is possible to launch the attack remotely. The exploit has been made available to the public and could be used for attacks. Upgrading to version 26.03.1 is able to address this issue. This patch is called 8a59895ba063040cc8dafd82e94024c406df3d04. It is advisable to upgrade the affected component. The vendor was contacted early, responded in a very professional manner and quickly released a fixed version of the affected product."
},
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"value": "Se ha identificado una debilidad en BookStackApp BookStack hasta la versión 26.03. Afecta a la función chapterToMarkdown del archivo app/Exports/ExportFormatter.php del componente Gestor de Exportación de Capítulos. La ejecución de una manipulación del argumento pages puede llevar a controles de acceso inadecuados. Es posible lanzar el ataque de forma remota. El exploit se ha puesto a disposición del público y podría utilizarse para ataques. La actualización a la versión 26.03.1 puede solucionar este problema. Este parche se denomina 8a59895ba063040cc8dafd82e94024c406df3d04. Es aconsejable actualizar el componente afectado. Se contactó al proveedor con antelación, respondió de manera muy profesional y lanzó rápidamente una versión corregida del producto afectado."
}
],
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