CVE-2021-41178
Nextcloud is an open-source, self-hosted productivity platform. Prior to versions 20.0.13, 21.0.5, and 22.2.0, a file traversal vulnerability makes an attacker able to download arbitrary SVG images from the host system, including user provided files. This could also be leveraged into a XSS/phishing attack, an attacker could upload a malicious SVG file that mimics the Nextcloud login form and send a specially crafted link to victims. The XSS risk here is mitigated due to the fact that Nextcloud employs a strict Content-Security-Policy disallowing execution of arbitrary JavaScript. It is recommended that the Nextcloud Server be upgraded to 20.0.13, 21.0.5 or 22.2.0. There are no known workarounds aside from upgrading.
CVSS
- Versión: 3.1
- Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N
- Puntuación base: 6.5
Probabilidad de explotación (EPSS)
- Probabilidad de explotación en los próximos 30 días: 1.78%
- Percentil entre todas las CVEs puntuadas: 78
- 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-23, CWE-434
- CWE-22
Referencias
- https://github.com/nextcloud/security-advisories/security/advisories/GHSA-jp9c-vpr3-m5rf
- https://github.com/nextcloud/server/pull/28726
- https://hackerone.com/reports/1302155
- https://security.gentoo.org/glsa/202208-17
- https://github.com/nextcloud/security-advisories/security/advisories/GHSA-jp9c-vpr3-m5rf
- https://github.com/nextcloud/server/pull/28726
- https://hackerone.com/reports/1302155
- https://security.gentoo.org/glsa/202208-17
JSON original (NVD)
Mostrar
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