CVE-2026-13723
A vulnerability in the `zipx.Unzip` extraction routine of Develar's app-builder allows an attacker to overwrite arbitrary files on macOS APFS by exploiting a Unicode Normalization Collision combined with symlink following behavior. APFS treats certain Unicode equivalent filenames as identical (e.g., ß ↔ ss), while app builder performs no canonical normalization before validating or writing paths. As a result, a crafted ZIP archive containing: • a symlink entry named ss pointing to a target file, and • a regular file named ß containing attacker controlled data, will cause the second write to follow the symlink and overwrite the target file.
CVSS
- Versión: 3.1
- Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:L
- Puntuación base: 6.5
Probabilidad de explotación (EPSS)
- Probabilidad de explotación en los próximos 30 días: 0.48%
- Percentil entre todas las CVEs puntuadas: 39
- Fecha de la puntuación: 5/10/2026
EPSS (Exploit Prediction Scoring System, de FIRST) estima la probabilidad de que una vulnerabilidad sea explotada en 30 días. Complementa a CVSS (impacto) y a CISA KEV (explotación confirmada).
Tecnologías afectadas (1)
⚠ Inferidas por IA a partir de la descripción — NVD aún no ha analizado esta CVE; no son CPE verificados.
CWE
- CWE-22, CWE-59
Referencias
JSON original (NVD)
Mostrar
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"options": [
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"version": "2.0.3",
"timestamp": "2026-07-29T18:21:31.256338Z"
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"integrityImpact": "LOW",
"userInteraction": "NONE",
"attackComplexity": "LOW",
"availabilityImpact": "LOW",
"privilegesRequired": "NONE",
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"affected": [
{
"source": "cret@cert.org",
"affectedData": [
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"version": "0",
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"published": "2026-07-29T18:16:50.603",
"references": [
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"source": "cret@cert.org"
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"url": "https://github.com/develar/app-builder",
"source": "cret@cert.org"
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"descriptions": [
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"value": "A vulnerability in the `zipx.Unzip` extraction routine of Develar's app-builder allows an attacker to overwrite arbitrary files on macOS APFS by exploiting a Unicode Normalization Collision combined with symlink following behavior. APFS treats certain Unicode equivalent filenames as identical (e.g., ß ↔ ss), while app builder performs no canonical normalization before validating or writing paths. As a result, a crafted ZIP archive containing:\r\n•\ta symlink entry named ss pointing to a target file, and\r\n•\ta regular file named ß containing attacker controlled data,\r\nwill cause the second write to follow the symlink and overwrite the target file."
}
],
"lastModified": "2026-07-30T19:10:06.847",
"sourceIdentifier": "cret@cert.org"
}