CVE-2025-21715

Published Feb 27, 2025

Last updated a year ago

CVSS high 7.8
Ubuntu

Overview

AI description

Automated description summarized from trusted sources.

CVE-2025-21715 is a use-after-free (UAF) vulnerability found in the Linux kernel's Davicom ethernet driver (dm9000). The vulnerability exists because the `dm` netdev private data is accessed after it has been freed by the `free_netdev()` call. This vulnerability was detected through static analysis and has been addressed by rearranging the driver code to ensure that `free_netdev()` is called last. The fix is similar to a previous patch for a comparable issue found in the Qualcomm emac driver.

Description
In the Linux kernel, the following vulnerability has been resolved: net: davicom: fix UAF in dm9000_drv_remove dm is netdev private data and it cannot be used after free_netdev() call. Using dm after free_netdev() can cause UAF bug. Fix it by moving free_netdev() at the end of the function. This is similar to the issue fixed in commit ad297cd2db89 ("net: qcom/emac: fix UAF in emac_remove"). This bug is detected by our static analysis tool.
Source
416baaa9-dc9f-4396-8d5f-8c081fb06d67
NVD status
Modified
Products
linux_kernel

Risk scores

CVSS 3.1

Type
Secondary
Base score
7.8
Impact score
5.9
Exploitability score
1.8
Vector string
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Severity
HIGH

Weaknesses

134c704f-9b21-4f2e-91b3-4a467353bcc0
CWE-416

Social media

Hype score
Not currently trending

  1. CVE-2025-21715 In the Linux kernel, the following vulnerability has been resolved: net: davicom: fix UAF in dm9000_drv_remove dm is netdev private data and it cannot be used after… https://t.co/pViuxnVH21

    @CVEnew

    27 Feb 2025

    800 Impressions

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    3 Likes

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Configurations

Related CVEs

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References

Sources include official advisories and independent security research.