CVE-2026-41401
libyang before 5.2.6 contains a heap use-after-free write vulnerability in lyd_parser_set_data_flags that incorrectly updates metadata list pointers when freeing non-head default metadata entries. Attackers can trigger this vulnerability by submitting crafted YANG XML documents with specific metadata attributes to applications parsing untrusted XML data, causing process crashes or potential code execution.
CVSS
- Versión: 4.0
- Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/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
- Puntuación base: 7.1
Probabilidad de explotación (EPSS)
- Probabilidad de explotación en los próximos 30 días: 0.64%
- Percentil entre todas las CVEs puntuadas: 49
- Fecha de la puntuación: 6/10/2026
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).
🎯 Técnicas ATT&CK
Cómo se explota esta vulnerabilidad y qué consigue el atacante, en el lenguaje de MITRE ATT&CK.
- Explotación
T1210Exploitation of Remote Serviceslateral movement75 % - Impacto principal
T1499.004Application or System Exploitationimpact70 % - Impacto secundario
T1059Command and Scripting Interpreterexecution45 %
AV:N/PR:L requiere red + privilegios, sugiriendo T1210. CWE-416 (use-after-free) causa DoS (crash) primariamente, con potencial de ejecución remota secundaria en contextos YANG XML.
Inferido por nuestro agente de análisis a partir de la descripción oficial, el vector CVSS y la CWE, y comprobado por un supervisor. Puede contener errores.
🛡️ Mitigaciones ATT&CK que cubren estas técnicas
Tecnologías afectadas (1)
⚠ Inferidas por IA a partir de la descripción — NVD aún no ha analizado esta CVE; no son CPE verificados.
CWE
- CWE-416
Referencias
- https://github.com/CESNET/libyang/commit/6b5ed47ee674fbe86b31bbebc4ff26889aeff38c
- https://github.com/CESNET/libyang/security/advisories/GHSA-9f49-8x56-jmjc
- https://red.anthropic.com/2026/cvd/findings/ANT-2026-TZQ1KH7E
- https://www.vulncheck.com/advisories/libyang-heap-use-after-free-write-in-xml-metadata-parsing
- https://github.com/CESNET/libyang/security/advisories/GHSA-9f49-8x56-jmjc
- https://red.anthropic.com/2026/cvd/findings/ANT-2026-TZQ1KH7E
JSON original (NVD)
Mostrar
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