Instituto Nacional de ciberseguridad. Sección Incibe
Instituto Nacional de Ciberseguridad. Sección INCIBE-CERT

CVE-2026-53503

Gravedad CVSS v3.1:
ALTA
Tipo:
CWE-20 Validación incorrecta de entrada
Fecha de publicación:
31/07/2026
Última modificación:
31/07/2026

Descripción

*** Pendiente de traducción *** Thumbor is an open-source photo thumbnail service by globo.com. Prior to 7.8.0, Thumbor's filters:convolution(, , ) filter passes the user-controlled value to a C extension (thumbor/ext/filters/_convolution.c) where it is used as a divisor (for % and /) without validating columns > 0. When columns=0, the C code triggers undefined behavior; on x86_64 this reliably results in a fatal divide-by-zero trap (SIGFPE) and crashes the Thumbor process, causing a remote denial of service. This issue is fixed in 7.8.0.