high CVSS 7.8

CVE-2025-21715·Kernel vulnerability

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.

Severity
high
Software
Kernel
Fixed in
6.13.2
Published
2025-02-27

Affected versions

From: 6.13

Until: 6.13.2

Fixed in: 6.13.2

How to fix this CVE

Update your Linux kernel to version 6.13.2 or later to resolve a use-after-free (UAF) vulnerability in the Davicom dm9000 network driver's removal function. The vulnerable code attempted to access driver private data after the network device had been freed, potentially causing kernel memory corruption or crashes. Apply this patch immediately if you are running kernel versions 6.13 through 6.13.1.

sudo dnf update kernel kernel-devel

Defensia detects this vulnerability

How to check if you are affected

  1. Step 1: Check your kernel version with `uname -r` and verify it falls in the range 6.13.0-6.13.1
  2. Step 2: Confirm the dm9000 driver is loaded by running `lsmod | grep dm9000` (presence indicates potential exposure if affected kernel version is running)
  3. Step 3: Search kernel logs for crash signatures with `dmesg | grep -i 'UAF\|use.*after.*free\|dm9000' and check /var/log/kern.log for memory corruption errors
  4. Step 4: After patching, verify with `uname -r` that kernel version is 6.13.2 or higher, then check for successful driver reload with `sudo modprobe -r dm9000 && sudo modprobe dm9000`

FAQ

What is CVE-2025-21715?

CVE-2025-21715 is a use-after-free vulnerability in the Linux kernel's Davicom dm9000 Ethernet driver where the device removal function attempted to access driver data structures after the network device had already been deallocated from memory. This could lead to kernel crashes or potential privilege escalation.

Is CVE-2025-21715 being actively exploited?

No, CVE-2025-21715 is not currently listed in CISA's Known Exploited Vulnerabilities catalog and no public exploits are available. However, the memory corruption potential warrants timely patching.

What versions of Kernel are affected by CVE-2025-21715?

Linux kernel versions 6.13.0 through 6.13.1 are vulnerable. The vulnerability was resolved in kernel version 6.13.2 and later.

How do I check if my server is vulnerable to CVE-2025-21715?

Run `uname -r` to check your kernel version; if it shows 6.13.0 or 6.13.1, you are vulnerable. Verify dm9000 driver presence with `lsmod | grep dm9000`.

Does Defensia detect CVE-2025-21715?

Yes — Defensia's CVE advisory scanner compares installed package versions against the NVD database. If Kernel is installed on a monitored server, CVE-2025-21715 will appear in your dashboard with remediation steps.

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CVE-2026-100075CVSS 9.8In the Linux kernel, the following vulnerability has been resolved: RDMA/srpt: Fix srpt_alloc_rw_ctxs() unwind counters When srpt_alloc_rw_ctxs() fails partway through a multi-buffer indirect descriptor, the unwind path destroys RDMA contexts but leaves stale n_rw_ctx and n_rdma values (and a dangling rw_ctxs pointer). Later sq_wr_avail accounting in srpt_queue_response() or srpt_write_pending() can then subtract the wrong number of send queue credits. Reset the counters and clear rw_ctxs after freeing the heap allocation before returning an error.
CVE-2026-64033CVSS 9.8In the Linux kernel, the following vulnerability has been resolved: RDMA/rtrs: Fix use-after-free in path file creation cleanup In the error path of rtrs_srv_create_path_files(), the sysfs root folders may already have been created and srv_path->kobj may already have been initialized. If a later step fails, the cleanup currently calls kobject_put(&srv_path->kobj) before rtrs_srv_destroy_once_sysfs_root_folders(srv_path). kobject_put() may drop the last reference to srv_path->kobj and invoke the release callback, rtrs_srv_release(), which frees srv_path. The following call to rtrs_srv_destroy_once_sysfs_root_folders(srv_path) then dereferences srv_path internally to access srv_path->srv, resulting in a use-after-free. This failure path is reached before rtrs_srv_create_path_files() returns success, so the successful-path lifetime handling is not involved. Fix this by destroying the sysfs root folders before calling kobject_put(&srv_path->kobj), so srv_path is still valid while the helper accesses it. This issue was found by a static analysis tool I am developing.
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References

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