5.3
MEDIUM CVSS 4.0
CVE-2026-71394
Heap Use of Uninitialized Memory in GNU Emacs for Android
Description

GNU Emacs for Android improperly validates the table header input in sfnt_read_table_directory() in src/sfnt.c. Due to an incorrect comparison variable in the read-length check, a crafted font file that claims to contain more table directory entries than actually present causes the parser to return a struct with uninitialized heap memory in the table directory entries. 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 leads to the use of uninitialized heap data in subsequent table lookups, potentially resulting in information disclosure, crashes, or arbitrary memory access on 32-bit targets. This issue is fixed after commit 7621ee1d01229d50e5c0cddea6bf0b01095a62cf

INFO

Published Date :

Aug. 10, 2026, 11:17 a.m.

Last Modified :

Aug. 10, 2026, 11:17 a.m.

Remotely Exploit :

Yes !
Affected Products

The following products are affected by CVE-2026-71394 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

ID Vendor Product Action
1 Gnu emacs
CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 4.0 MEDIUM 4bb8329e-dd38-46c1-aafb-9bf32bcb93c6
CVSS 4.0 MEDIUM [email protected]
Solution
Update GNU Emacs for Android to address heap memory corruption vulnerability in sfnt.c.
  • Update GNU Emacs for Android to the latest version.
  • Apply the patch referenced by commit 7621ee1d01229d50e5c0cddea6bf0b01095a62cf.
References to Advisories, Solutions, and Tools

Here, you will find a curated list of external links that provide in-depth information, practical solutions, and valuable tools related to CVE-2026-71394.

URL Resource
https://cert.pl/en/posts/2026/08/CVE-2026-71391
https://www.gnu.org/savannah-checkouts/gnu/emacs/emacs.html
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-71394 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2026-71394 weaknesses.

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2026-71394 vulnerability anywhere in the article.

  • cert.pl
Vulnerabilities in GNU Emacs software

Vulnerabilities in GNU Emacs software CVE ID CVE-2026-71391 Publication date 10 August 2026 Vendor GNU Product Emacs Vulnerable versions All through 30.2 Vulnerability type (CWE) Off-by-one Error (CWE ... Read more

Published Date: Aug 10, 2026 (3 hours, 41 minutes ago)

The following table lists the changes that have been made to the CVE-2026-71394 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • New CVE Received by [email protected]

    Aug. 10, 2026

    Action Type Old Value New Value
    Added Affected [{'repo': 'https://cgit.git.savannah.gnu.org/cgit/emacs.git', 'vendor': 'GNU', 'product': 'Emacs', 'versions': [{'status': 'affected', 'changes': [{'at': 'commit 7621ee1d01229d50e5c0cddea6bf0b01095a62cf', 'status': 'unaffected'}], 'version': '0', 'versionType': 'custom', 'lessThanOrEqual': '30.2'}], 'platforms': ['Android'], 'programFiles': ['src/sfnt.c'], 'defaultStatus': 'unaffected'}]
    Added Description GNU Emacs for Android improperly validates the table header input in sfnt_read_table_directory() in src/sfnt.c. Due to an incorrect comparison variable in the read-length check, a crafted font file that claims to contain more table directory entries than actually present causes the parser to return a struct with uninitialized heap memory in the table directory entries. 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 leads to the use of uninitialized heap data in subsequent table lookups, potentially resulting in information disclosure, crashes, or arbitrary memory access on 32-bit targets. This issue is fixed after commit 7621ee1d01229d50e5c0cddea6bf0b01095a62cf
    Added CVSS V4.0 AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:L/SC:L/SI:L/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
    Added CWE CWE-1284
    Added Reference https://cert.pl/en/posts/2026/08/CVE-2026-71391
    Added Reference https://www.gnu.org/savannah-checkouts/gnu/emacs/emacs.html
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.