CVE-2026-71393

GNU Emacs for Android is vulnerable to an integer overflow in sfnt_read_name_table() in src/sfnt.c. The function computes an allocation size using a 32-bit length value from a TrueType font file without overflow checking. On 32-bit targets, a crafted font causes the calculation to wrap, resulting in an undersized heap allocation. A subsequent read() call writes beyond the buffer, causing a heap buffer overflow. An attacker can deliver a malicious font file via email, EWW (Emacs Web Wowser), or documents with custom faces, causing Emacs to load it. This can lead to heap memory corruption and potential code execution. This issue was fixed in commit d51a4722316efe0960994d371e1859099894d1ca

CVSS

No CVSS.

References

Link	Resource
https://cert.pl/en/posts/2026/08/CVE-2026-71391
https://git.savannah.gnu.org/cgit/emacs.git/commit/?id=d51a4722316efe0960994d371e1859099894d1ca
https://www.gnu.org/savannah-checkouts/gnu/emacs/emacs.html

Configurations

No configuration.

History

23 Oct 2026, 20:10

Type	Values Removed	Values Added
Summary		(es) GNU Emacs para Android es vulnerable a un desbordamiento de entero en sfnt_read_name_table() en src/sfnt.c. La función calcula un tamaño de asignación utilizando un valor de longitud de 32 bits de un archivo de fuente TrueType sin comprobación de desbordamiento. En objetivos de 32 bits, una fuente manipulada hace que el cálculo se ajuste, lo que resulta en una asignación de montón de tamaño insuficiente. Una llamada posterior a read() escribe más allá del búfer, causando un desbordamiento de búfer de montón. Un atacante puede entregar un archivo de fuente malicioso a través de correo electrónico, EWW (Emacs Web Wowser), o documentos con caras personalizadas, haciendo que Emacs lo cargue. Esto puede llevar a corrupción de memoria de montón y potencial ejecución de código. Este problema fue solucionado en el commit d51a4722316efe0960994d371e1859099894d1ca

Information

Published : 2026-08-10 11:17

Updated : 2026-10-24 15:10

NVD link : CVE-2026-71393

Mitre link : CVE-2026-71393

CVE.ORG link : CVE-2026-71393

JSON object : View

Products Affected

No product.

CWE

CWE-190

Integer Overflow or Wraparound

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