medium CVSS 5.5

CVE-2024-36976·Kernel vulnerability

In the Linux kernel, the following vulnerability has been resolved: Revert "media: v4l2-ctrls: show all owned controls in log_status" This reverts commit 9801b5b28c6929139d6fceeee8d739cc67bb2739. This patch introduced a potential deadlock scenario: [Wed May 8 10:02:06 2024] Possible unsafe locking scenario: [Wed May 8 10:02:06 2024] CPU0 CPU1 [Wed May 8 10:02:06 2024] ---- ---- [Wed May 8 10:02:06 2024] lock(vivid_ctrls:1620:(hdl_vid_cap)->_lock); [Wed May 8 10:02:06 2024] lock(vivid_ctrls:1608:(hdl_user_vid)->_lock); [Wed May 8 10:02:06 2024] lock(vivid_ctrls:1620:(hdl_vid_cap)->_lock); [Wed May 8 10:02:06 2024] lock(vivid_ctrls:1608:(hdl_user_vid)->_lock); For now just revert.

Severity
medium
Software
Kernel
Fixed in
6.9.2
Published
2024-06-18

Affected versions

From: 6.9

Until: 6.9.2

Fixed in: 6.9.2

How to fix this CVE

Update your Linux kernel to version 6.9.2 or later to resolve a deadlock condition in the v4l2-ctrls subsystem. This vulnerability affects kernel versions 6.9 through 6.9.2 and was introduced by a media control logging enhancement that created unsafe lock acquisition patterns. Systems running affected kernel versions should prioritize this update to restore system stability and prevent potential denial-of-service conditions.

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 compare against the affected range (6.9.0 to 6.9.2)
  2. Step 2: Verify if v4l2 media controls are in use by checking `lsmod | grep videobuf` or `lsmod | grep v4l2`
  3. Step 3: Search kernel logs for deadlock warnings using `journalctl -xe | grep -i deadlock` or `dmesg | grep -i deadlock`
  4. Step 4: After patching, confirm the new kernel version with `uname -r` and reboot if kernel was updated

FAQ

What is CVE-2024-36976?

This CVE addresses a kernel deadlock vulnerability in the video4linux2 (v4l2) control subsystem caused by nested lock acquisition on multiple control handler mutexes. The issue stems from a change intended to improve control logging that inadvertently created circular lock dependencies.

Is CVE-2024-36976 being actively exploited?

No, this vulnerability is not listed in CISA's Known Exploited Vulnerabilities catalog and no public exploits are available. However, it can be triggered locally to cause denial-of-service through system hang.

What versions of Kernel are affected by CVE-2024-36976?

Linux kernel versions 6.9.0, 6.9.1, and 6.9.2 are affected. The fix is available in kernel 6.9.2 and later stable releases.

How do I check if my server is vulnerable to CVE-2024-36976?

Run `uname -r` to display your kernel version. If it shows 6.9.0, 6.9.1, or 6.9.2, your system is vulnerable. For exact version details, check `cat /proc/version` as well.

Does Defensia detect CVE-2024-36976?

Yes — Defensia's CVE advisory scanner compares installed package versions against the NVD database. If the Linux kernel package is installed on a monitored server, CVE-2024-36976 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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