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

No history.

Information

Published : 2026-08-10 11:17

Updated : 2026-08-28 15:26

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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