CVE-2025-21840 (GCVE-0-2025-21840)

Vulnerability from cvelistv5 – Published: 2025-03-07 09:09 – Updated: 2026-05-11 21:07
VLAI
Title
thermal/netlink: Prevent userspace segmentation fault by adjusting UAPI header
Summary
In the Linux kernel, the following vulnerability has been resolved: thermal/netlink: Prevent userspace segmentation fault by adjusting UAPI header The intel-lpmd tool [1], which uses the THERMAL_GENL_ATTR_CPU_CAPABILITY attribute to receive HFI events from kernel space, encounters a segmentation fault after commit 1773572863c4 ("thermal: netlink: Add the commands and the events for the thresholds"). The issue arises because the THERMAL_GENL_ATTR_CPU_CAPABILITY raw value was changed while intel_lpmd still uses the old value. Although intel_lpmd can be updated to check the THERMAL_GENL_VERSION and use the appropriate THERMAL_GENL_ATTR_CPU_CAPABILITY value, the commit itself is questionable. The commit introduced a new element in the middle of enum thermal_genl_attr, which affects many existing attributes and introduces potential risks and unnecessary maintenance burdens for userspace thermal netlink event users. Solve the issue by moving the newly introduced THERMAL_GENL_ATTR_TZ_PREV_TEMP attribute to the end of the enum thermal_genl_attr. This ensures that all existing thermal generic netlink attributes remain unaffected. [ rjw: Subject edits ]
Severity
5.5 (Medium)
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Assigner
Linux CNA under the mitre root
CNA scorecard D 53/100 over 6638 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
Linux Linux Affected: 1773572863c43a14a3e45f0591f28b7dec1ee52a , < 3a4ca365c51729143a2cab693cd40fe0bb585ef0 (git)
Affected: 1773572863c43a14a3e45f0591f28b7dec1ee52a , < c195b9c6ab9c383d7aa3f4a65879b3ca90cb378b (git)
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Linux Linux Affected: 6.13
Unaffected: 0 , < 6.13 (semver)
Unaffected: 6.13.4 , ≤ 6.13.* (semver)
Unaffected: 6.14 , ≤ * (original_commit_for_fix)
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            "value": "En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: thermal/netlink: Prevenir un error de segmentaci\u00f3n del espacio de usuario ajustando el encabezado UAPI La herramienta intel-lpmd [1], que utiliza el atributo THERMAL_GENL_ATTR_CPU_CAPABILITY para recibir eventos HFI desde el espacio del kernel, encuentra un error de segmentaci\u00f3n despu\u00e9s de el commit 1773572863c4 (\"thermal: netlink: Agregar los comandos y los eventos para los umbrales\"). El problema surge porque se cambi\u00f3 el valor sin procesar de THERMAL_GENL_ATTR_CPU_CAPABILITY mientras que intel_lpmd todav\u00eda usa el valor anterior. Aunque intel_lpmd se puede actualizar para verificar THERMAL_GENL_VERSION y usar el valor THERMAL_GENL_ATTR_CPU_CAPABILITY apropiado, el commit en s\u00ed es cuestionable. El commit introdujo un nuevo elemento en el medio de la enumeraci\u00f3n thermal_genl_attr, que afecta a muchos atributos existentes e introduce riesgos potenciales y cargas de mantenimiento innecesarias para los usuarios del evento de enlace de red t\u00e9rmico del espacio de usuario. Resuelva el problema moviendo el atributo THERMAL_GENL_ATTR_TZ_PREV_TEMP recientemente introducido al final de la enumeraci\u00f3n thermal_genl_attr. Esto garantiza que todos los atributos de enlace de red gen\u00e9ricos t\u00e9rmicos existentes permanezcan inalterados. [ rjw: Ediciones del sujeto ]"
          }
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        "id": "CVE-2025-21840",
        "lastModified": "2026-06-17T08:44:24.957",
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}



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