CVE-2025-21995

Status: ModifiedMedium (5.5)—
In the Linux kernel, the following vulnerability has been resolved:
drm/sched: Fix fence reference count leak
The last_scheduled fence leaks when an entity is being killed and adding the cleanup callback fails.
Decrement the reference count of prev when dma_fence_add_callback() fails, ensuring proper balance.
[phasta: add git tag info for stable kernel]
CVSS

Version: 3.1
Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Base score: 5.5
Exploitation probability (EPSS)

Probability of exploitation in the next 30 days: 0.19%
Percentile among all scored CVEs: 8
Score date: 10/5/2026
EPSS (Exploit Prediction Scoring System, FIRST) estimates how likely a vulnerability is to be exploited in the wild within 30 days. It complements CVSS (impact) and CISA KEV (confirmed exploitation).
Affected technologies (1)

Linux — Linux Kernel
CWEs

NVD-CWE-Other
References

Raw JSON (NVD)

Show
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      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\ndrm/sched: Fix fence reference count leak\n\nThe last_scheduled fence leaks when an entity is being killed and adding\nthe cleanup callback fails.\n\nDecrement the reference count of prev when dma_fence_add_callback()\nfails, ensuring proper balance.\n\n[phasta: add git tag info for stable kernel]"
    },
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      "value": "En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: drm/sched: Se corrige la fuga del recuento de referencias de la valla. La valla last_scheduled se filtra cuando se elimina una entidad y falla la devolución de llamada de limpieza. Se reduce el recuento de referencias de prev cuando dma_fence_add_callback() falla, asegurando un equilibrio adecuado. [phasta: se añade información de la etiqueta Git para el kernel estable]"
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