CVE-2018-6917

En FreeBSD, en versiones anteriores a 11.1-STABLE, 11.1-RELEASE-p9, 10.4-STABLE, 10.4-RELEASE-p8 y 10.3-RELEASE-p28, la validación insuficiente de parámetros de fuente proporcionados por el usuario pueden resultar en un desbordamiento de enteros que conduce al uso de memoria arbitraria del kernel como datos glyph. Los usuarios sin privilegios podrían ser capaces de acceder a datos privilegiados del kernel.

Insufficient validation of user-provided font parameters can result in an integer overflow, leading to the use of arbitrary kernel memory as glyph data. Characters that reference this data can be displayed on the screen, effectively disclosing kernel memory. Unprivileged users may be able to access privileged kernel data. Such memory might contain sensitive information, such as portions of the file cache or terminal buffers. This information might be directly useful, or it might be leveraged to obtain elevated privileges in some way; for example, a terminal buffer might include a user-entered password.