high CVSS 7

CVE-2024-50059·Kernel vulnerability

In the Linux kernel, the following vulnerability has been resolved: ntb: ntb_hw_switchtec: Fix use after free vulnerability in switchtec_ntb_remove due to race condition In the switchtec_ntb_add function, it can call switchtec_ntb_init_sndev function, then &sndev->check_link_status_work is bound with check_link_status_work. switchtec_ntb_link_notification may be called to start the work. If we remove the module which will call switchtec_ntb_remove to make cleanup, it will free sndev through kfree(sndev), while the work mentioned above will be used. The sequence of operations that may lead to a UAF bug is as follows: CPU0 CPU1 | check_link_status_work switchtec_ntb_remove | kfree(sndev); | | if (sndev->link_force_down) | // use sndev Fix it by ensuring that the work is canceled before proceeding with the cleanup in switchtec_ntb_remove.

Severity
high
Software
Kernel
Fixed in
6.11.4
Published
2024-10-21

Affected versions

From: 6.7

Until: 6.11.4

Fixed in: 6.11.4

How to fix this CVE

Update your Linux kernel to version 6.11.4 or later to resolve a use-after-free vulnerability in the NTB Switchtec driver that can occur when the kernel module is removed while background link-status checks are still running. This race condition allows freed memory to be accessed by a scheduled work queue, potentially causing system instability or information disclosure. Apply the kernel update through your distribution's package manager and reboot your system to activate the patched kernel.

sudo dnf update kernel kernel-devel && sudo reboot

Defensia detects this vulnerability

How to check if you are affected

  1. Step 1: Check your current kernel version by running `uname -r` and compare against the affected range (6.7 to 6.11.3)
  2. Step 2: Verify if the Switchtec NTB driver is loaded by executing `lsmod | grep switchtec_ntb` — if output appears, the vulnerable component is present
  3. Step 3: Search system logs for UAF-related kernel warnings using `sudo dmesg | grep -i 'use-after-free\|UAF\|bad-access'` or check `/var/log/kern.log`
  4. Step 4: After patching, confirm the new kernel is active with `uname -r` showing version 6.11.4 or later, and verify the module reloads cleanly by unloading and reloading it: `sudo modprobe -r switchtec_ntb && sudo modprobe switchtec_ntb`

FAQ

What is CVE-2024-50059?

CVE-2024-50059 is a use-after-free vulnerability in the Linux kernel's NTB Switchtec driver where the kernel module frees driver memory while a background work queue is still scheduled to access it, creating a race condition that can cause memory corruption or system crashes.

Is CVE-2024-50059 being actively exploited?

No, CVE-2024-50059 is not listed as actively exploited in the CISA Known Exploited Vulnerabilities catalog, and no public exploits have been disclosed.

What versions of Kernel are affected by CVE-2024-50059?

Linux kernel versions 6.7 through 6.11.3 are vulnerable; version 6.11.4 and later contain the fix.

How do I check if my server is vulnerable to CVE-2024-50059?

Run `uname -r` to check your kernel version — if it shows 6.7.x through 6.11.3, you are vulnerable. Additionally, confirm the Switchtec NTB driver is in use with `lsmod | grep switchtec_ntb`.

Does Defensia detect CVE-2024-50059?

Yes — Defensia's CVE advisory scanner compares installed package versions against the NVD database. If the Linux kernel is installed on a monitored server, CVE-2024-50059 will appear in your dashboard with remediation steps.

Related Kernel CVEs

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CVE-2024-36031CVSS 9.8In the Linux kernel, the following vulnerability has been resolved: keys: Fix overwrite of key expiration on instantiation The expiry time of a key is unconditionally overwritten during instantiation, defaulting to turn it permanent. This causes a problem for DNS resolution as the expiration set by user-space is overwritten to TIME64_MAX, disabling further DNS updates. Fix this by restoring the condition that key_set_expiry is only called when the pre-parser sets a specific expiry.
CVE-2024-38612CVSS 9.8In the Linux kernel, the following vulnerability has been resolved: ipv6: sr: fix invalid unregister error path The error path of seg6_init() is wrong in case CONFIG_IPV6_SEG6_LWTUNNEL is not defined. In that case if seg6_hmac_init() fails, the genl_unregister_family() isn't called. This issue exist since commit 46738b1317e1 ("ipv6: sr: add option to control lwtunnel support"), and commit 5559cea2d5aa ("ipv6: sr: fix possible use-after-free and null-ptr-deref") replaced unregister_pernet_subsys() with genl_unregister_family() in this error path.
CVE-2024-38623CVSS 9.8In the Linux kernel, the following vulnerability has been resolved: fs/ntfs3: Use variable length array instead of fixed size Should fix smatch warning: ntfs_set_label() error: __builtin_memcpy() 'uni->name' too small (20 vs 256)
CVE-2021-47548CVSS 9.8In the Linux kernel, the following vulnerability has been resolved: ethernet: hisilicon: hns: hns_dsaf_misc: fix a possible array overflow in hns_dsaf_ge_srst_by_port() The if statement: if (port >= DSAF_GE_NUM) return; limits the value of port less than DSAF_GE_NUM (i.e., 8). However, if the value of port is 6 or 7, an array overflow could occur: port_rst_off = dsaf_dev->mac_cb[port]->port_rst_off; because the length of dsaf_dev->mac_cb is DSAF_MAX_PORT_NUM (i.e., 6). To fix this possible array overflow, we first check port and if it is greater than or equal to DSAF_MAX_PORT_NUM, the function returns.

References

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