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

23 Oct 2026, 20:10

Type	Values Removed	Values Added
Summary		(es) GNU Emacs para Android es vulnerable a un desbordamiento de entero en la función sfnt_read_cmap_format_12() en src/sfnt.c. Al procesar un archivo de fuente TrueType manipulado, una adición no protegida en la llamada de asignación xmalloc se desborda en compilaciones de 32 bits, causando una escritura de desbordamiento de búfer de pila. Un atacante puede entregar un archivo de fuente malicioso a través de correo electrónico, EWW (Emacs Web Wowser) o documentos con caras personalizadas, haciendo que Emacs lo cargue. Esto resulta en corrupción de memoria de pila que puede conducir a la ejecución de código. Este problema fue solucionado en el commit c4e20777c26548722a37b03db93243e83a0d6188

Information

Published : 2026-08-10 11:17

Updated : 2026-10-24 15:10

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

{"id": "CVE-2026-71392", "cveTags": [], "metrics": {"ssvcV203": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "ssvcData": {"id": "CVE-2026-71392", "role": "CISA Coordinator", "options": [{"exploitation": "none"}, {"automatable": "no"}, {"technicalImpact": "partial"}], "version": "2.0.3", "timestamp": "2026-08-10T17:48:48.416617Z"}}], "cvssMetricV40": [{"type": "Secondary", "source": "cvd@cert.pl", "cvssData": {"Safety": "NOT_DEFINED", "version": "4.0", "Recovery": "NOT_DEFINED", "baseScore": 5.3, "Automatable": "NOT_DEFINED", "attackVector": "NETWORK", "baseSeverity": "MEDIUM", "valueDensity": "NOT_DEFINED", "vectorString": "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/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", "exploitMaturity": "NOT_DEFINED", "providerUrgency": "NOT_DEFINED", "userInteraction": "PASSIVE", "attackComplexity": "LOW", "attackRequirements": "NONE", "privilegesRequired": "NONE", "subIntegrityImpact": "LOW", "vulnIntegrityImpact": "NONE", "integrityRequirement": "NOT_DEFINED", "modifiedAttackVector": "NOT_DEFINED", "subAvailabilityImpact": "NONE", "vulnAvailabilityImpact": "LOW", "availabilityRequirement": "NOT_DEFINED", "modifiedUserInteraction": "NOT_DEFINED", "modifiedAttackComplexity": "NOT_DEFINED", "subConfidentialityImpact": "NONE", "vulnConfidentialityImpact": "NONE", "confidentialityRequirement": "NOT_DEFINED", "modifiedAttackRequirements": "NOT_DEFINED", "modifiedPrivilegesRequired": "NOT_DEFINED", "modifiedSubIntegrityImpact": "NOT_DEFINED", "modifiedVulnIntegrityImpact": "NOT_DEFINED", "vulnerabilityResponseEffort": "NOT_DEFINED", "modifiedSubAvailabilityImpact": "NOT_DEFINED", "modifiedVulnAvailabilityImpact": "NOT_DEFINED", "modifiedSubConfidentialityImpact": "NOT_DEFINED", "modifiedVulnConfidentialityImpact": "NOT_DEFINED"}}]}, "affected": [{"source": "cvd@cert.pl", "affectedData": [{"repo": "https://cgit.git.savannah.gnu.org/cgit/emacs.git", "vendor": "GNU", "product": "Emacs", "versions": [{"status": "affected", "changes": [{"at": "commit c4e20777c26548722a37b03db93243e83a0d6188", "status": "unaffected"}], "version": "0", "versionType": "custom", "lessThanOrEqual": "30.2"}], "platforms": ["Android", "32 bit"], "programFiles": ["src/sfnt.c"], "defaultStatus": "unaffected"}]}], "published": "2026-08-10T11:17:28.397", "references": [{"url": "https://cert.pl/en/posts/2026/08/CVE-2026-71391", "source": "cvd@cert.pl"}, {"url": "https://git.savannah.gnu.org/cgit/emacs.git/commit/?id=c4e20777c26548722a37b03db93243e83a0d6188", "source": "cvd@cert.pl"}, {"url": "https://www.gnu.org/savannah-checkouts/gnu/emacs/emacs.html", "source": "cvd@cert.pl"}], "vulnStatus": "Deferred", "weaknesses": [{"type": "Secondary", "source": "cvd@cert.pl", "description": [{"lang": "en", "value": "CWE-190"}]}], "descriptions": [{"lang": "en", "value": "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\u00a0results in heap memory corruption that can lead to code execution.\n\n\nThis issue was fixed in commit c4e20777c26548722a37b03db93243e83a0d6188"}, {"lang": "es", "value": "GNU Emacs para Android es vulnerable a un desbordamiento de entero en la funci\u00f3n sfnt_read_cmap_format_12() en src/sfnt.c. Al procesar un archivo de fuente TrueType manipulado, una adici\u00f3n no protegida en la llamada de asignaci\u00f3n xmalloc se desborda en compilaciones de 32 bits, causando una escritura de desbordamiento de b\u00fafer de pila. Un atacante puede entregar un archivo de fuente malicioso a trav\u00e9s de correo electr\u00f3nico, EWW (Emacs Web Wowser) o documentos con caras personalizadas, haciendo que Emacs lo cargue. Esto resulta en corrupci\u00f3n de memoria de pila que puede conducir a la ejecuci\u00f3n de c\u00f3digo.\n\nEste problema fue solucionado en el commit c4e20777c26548722a37b03db93243e83a0d6188"}], "lastModified": "2026-10-24T15:10:00.190", "sourceIdentifier": "cvd@cert.pl"}