CVE-2026-71392

GNU Emacs for Android is vulnerable to an integer overflow in the sfnt_read_cmap_format_12() function in src/sfnt.c. When processing a crafted TrueType font file, an unguarded addition in the xmalloc allocation call wraps around on 32-bit builds, causing a heap buffer overflow write. 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 results in heap memory corruption that can lead to code execution. This issue was fixed in commit c4e20777c26548722a37b03db93243e83a0d6188

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=c4e20777c26548722a37b03db93243e83a0d6188
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-2026-71392

Mitre link : CVE-2026-71392

CVE.ORG link : CVE-2026-71392

JSON object : View

Products Affected

No product.

CWE

CWE-190

Integer Overflow or Wraparound

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