CVE-2026-71391: medium-severity vulnerability in GNU Emacs
Off-by-One Error in GNU Emacs for Android
Published
E-mail alert when it lands in KEV, gets a public PoC or its score goes up.
13Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 5.3epss 0.5%
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
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:N/SC:L/SI:N/SA:N
Affected products
GNU · EmacsRelated CVEs — GNU Emacs
In the same product, most dangerous first.
CVE-2026-71393MEDIUMHeap Buffer Overflow in GNU Emacs for AndroidEPSS 0.7%CVE-2026-71392MEDIUMInteger Overflow in GNU Emacs for AndroidEPSS 0.7%CVE-2026-108976HIGHCVE-2026-108976EPSS 0.6%CVE-2026-71394MEDIUMHeap Use of Uninitialized Memory in GNU Emacs for AndroidEPSS 0.4%CVE-2026-96269HIGHCVE-2026-96269EPSS 0.1%CVE-2026-77219MEDIUMGNU Emacs < 31.0.91 Heap Over-Read via PBM/PPM/PGM Image LoaderEPSS 0.1%