CVE-2026-71391
published 2026-08-10CVE-2026-71391: GNU Emacs for Android contains an off-by-one error in the gvar table parser in src/sfnt.c. The shared-coordinate index boundary check in…
PriorityP432medium5.3CVSS 4.0
AVNACLATNPRNUIPVCNVINVANSCLSINSANEXCRXIRXARXMAVXMACXMATXMPRXMUIXMVCXMVIXMVAXMSCXMSIXMSAXSXAUXRXVXREXUX
EPSS
0.33%
25.6th percentile
GNU Emacs for Android contains an off-by-one error in the gvar table parser in src/sfnt.c. The shared-coordinate index boundary check in sfnt_vary_simple_glyph() and sfnt_vary_compound_glyph() uses a strict greater-than comparison instead of greater-than-or-equal, allowing a crafted TrueType variable font to bypass the check and trigger a heap-based out-of-bounds read via memcpy. 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 exposes heap memory contents which can be later used to defeat ASLR.
This issue was fixed in commit 95ab9ef627b212d74d321c5bbb5b56a1be7b9fbe
Affected
1 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| gnu | emacs | <= 30.2 | — |
CVSS provenance
nvdv4.05.3MEDIUMCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:N/SC:L/SI:N/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
vendor_redhat5.3MEDIUM
Stop checking back — get the weekly exploitation signal.
Every Monday: what got weaponized or added to CISA KEV in the last seven days — each CVE cross-linked to its PoC, Nuclei template, and detection rule. Free, one email a week, unsubscribe in one click.
GHSA
GNU Emacs for Android contains an off-by-one error in the gvar table parser in src/sfnt.c.
ghsa_unreviewed·2026-08-10
CVE-2026-71391 [MEDIUM] CWE-193 GNU Emacs for Android contains an off-by-one error in the gvar table parser in src/sfnt.c.
GNU Emacs for Android contains an off-by-one error in the gvar table parser in src/sfnt.c. The shared-coordinate index boundary check in sfnt_vary_simple_glyph() and sfnt_vary_compound_glyph() uses a strict greater-than comparison instead of greater-than-or-equal, allowing a crafted TrueType variable font to bypass the check and trigger a heap-based out-of-bounds read via memcpy. 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 exposes heap memory contents which can be later used to defeat ASLR.
This issue was fixed in commit 95ab9ef627b212d74d321c5bbb5b56a1be7b9fbe
Red Hat
emacs: off-by-one error via a malicious font file
vendor_redhat·2026-08-10·CVSS 5.3
CVE-2026-71391 [MEDIUM] CWE-193 emacs: off-by-one error via a malicious font file
emacs: off-by-one error via a malicious font file
GNU Emacs for Android contains an off-by-one error in the gvar table parser in src/sfnt.c. The shared-coordinate index boundary check in sfnt_vary_simple_glyph() and sfnt_vary_compound_glyph() uses a strict greater-than comparison instead of greater-than-or-equal, allowing a crafted TrueType variable font to bypass the check and trigger a heap-based out-of-bounds read via memcpy. 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 exposes heap memory contents which can be later used to defeat ASLR.
This issue was fixed in commit 95ab9ef627b212d74d321c5bbb5b56a1be7b9fbe
A flaw was found in GNU Emacs for Android. An off-by-one error in the gvar table
No detection rules found.
No public exploits indexed.
2026-08-10
Published