CVE-2025-21976
Estado: ModificadaMedia (5.5)—
In the Linux kernel, the following vulnerability has been resolved:
fbdev: hyperv_fb: Allow graceful removal of framebuffer
When a Hyper-V framebuffer device is unbind, hyperv_fb driver tries to release the framebuffer forcefully. If this framebuffer is in use it produce the following WARN and hence this framebuffer is never released.
Fix this by moving the release of framebuffer and assosiated memory to fb_ops.fb_destroy function, so that framebuffer framework handles it gracefully.
While we fix this, also replace manual registrations/unregistration of framebuffer with devm_register_framebuffer.
Detalles técnicos trazas, registros y código del informe original
[ 44.111220] WARNING: CPU: 35 PID: 1882 at drivers/video/fbdev/core/fb_info.c:70 framebuffer_release+0x2c/0x40 < snip > [ 44.111289] Call Trace: [ 44.111290] <TASK> [ 44.111291] ? show_regs+0x6c/0x80 [ 44.111295] ? __warn+0x8d/0x150 [ 44.111298] ? framebuffer_release+0x2c/0x40 [ 44.111300] ? report_bug+0x182/0x1b0 [ 44.111303] ? handle_bug+0x6e/0xb0 [ 44.111306] ? exc_invalid_op+0x18/0x80 [ 44.111308] ? asm_exc_invalid_op+0x1b/0x20 [ 44.111311] ? framebuffer_release+0x2c/0x40 [ 44.111313] ? hvfb_remove+0x86/0xa0 [hyperv_fb] [ 44.111315] vmbus_remove+0x24/0x40 [hv_vmbus] [ 44.111323] device_remove+0x40/0x80 [ 44.111325] device_release_driver_internal+0x20b/0x270 [ 44.111327] ? bus_find_device+0xb3/0xf0
CVSS
- Versión: 3.1
- Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
- Puntuación base: 5.5
Probabilidad de explotación (EPSS)
- Probabilidad de explotación en los próximos 30 días: 0.20%
- Percentil entre todas las CVEs puntuadas: 8
- 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).
Tecnologías afectadas (1)
CWE
- NVD-CWE-noinfo
Referencias
JSON original (NVD)
Mostrar
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"value": "En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: fbdev: hyperv_fb: Permite la eliminación ordenada del framebuffer. Cuando se desvincula un dispositivo framebuffer de Hyper-V, el controlador hyperv_fb intenta liberarlo forzosamente. Si este framebuffer está en uso, genera la siguiente advertencia y, por lo tanto, nunca se libera. [44.111220] ADVERTENCIA: CPU: 35 PID: 1882 en drivers/video/fbdev/core/fb_info.c:70 framebuffer_release+0x2c/0x40 < snip > [44.111289] Rastreo de llamadas: [ 44.111290] [ 44.111291] ? show_regs+0x6c/0x80 [ 44.111295] ? __warn+0x8d/0x150 [ 44.111298] ? framebuffer_release+0x2c/0x40 [ 44.111300] ? report_bug+0x182/0x1b0 [ 44.111303] ? handle_bug+0x6e/0xb0 [ 44.111306] ? exc_invalid_op+0x18/0x80 [ 44.111308] ? asm_exc_invalid_op+0x1b/0x20 [ 44.111311] ? framebuffer_release+0x2c/0x40 [ 44.111313] ? hvfb_remove+0x86/0xa0 [hyperv_fb] [ 44.111315] vmbus_remove+0x24/0x40 [hv_vmbus] [ 44.111323] device_remove+0x40/0x80 [ 44.111325] device_release_driver_internal+0x20b/0x270 [ 44.111327] ? bus_find_device+0xb3/0xf0. Solucione esto trasladando la liberación del framebuffer y la memoria asociada a la función fb_ops.fb_destroy, para que el framework del framebuffer lo gestione correctamente. Mientras lo solucionamos, también reemplace el registro/desregistro manual del framebuffer con devm_register_framebuffer."
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"lastModified": "2026-07-30T06:22:01.277",
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