Vulnerability · Published Aug 10, 2026 · Assigned by CERT-PL
CVE-2026-71393Heap Buffer Overflow in GNU Emacs for Android
Medium 5.3
In plain English
A medium-severity integer overflow in Emacs from GNU. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.7% (higher than 52% of all known vulnerabilities).
Official description
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
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian:12 | emacs | no fix listed | DEBIAN-CVE-2026-71393 |
| Debian:13 | emacs | no fix listed | DEBIAN-CVE-2026-71393 |
| Debian:14 | emacs | no fix listed | DEBIAN-CVE-2026-71393 |
| Ubuntu:26.10 | emacs | no fix listed | UBUNTU-CVE-2026-71393 |
| Ubuntu:22.04:LTS | xemacs21 | no fix listed | UBUNTU-CVE-2026-71393 |
| Ubuntu:24.04:LTS | xemacs21 | no fix listed | UBUNTU-CVE-2026-71393 |
| Ubuntu:26.04:LTS | xemacs21 | no fix listed | UBUNTU-CVE-2026-71393 |
| Ubuntu:26.10 | xemacs21 | no fix listed | UBUNTU-CVE-2026-71393 |
| Ubuntu:22.04:LTS | xemacs21-packages | no fix listed | UBUNTU-CVE-2026-71393 |
| Ubuntu:24.04:LTS | xemacs21-packages | no fix listed | UBUNTU-CVE-2026-71393 |
| Ubuntu:26.04:LTS | xemacs21-packages | no fix listed | UBUNTU-CVE-2026-71393 |
| Ubuntu:26.10 | xemacs21-packages | no fix listed | UBUNTU-CVE-2026-71393 |
Affected products (as reported)
Weakness: CWE-190 · Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:L/SC:N/SI:L/SA:N