CVE-2026-74680: Linux kernel · usb: atm: cxacru: properly kill rcv_urb on error in cxacru_cm()
Affects Linux kernelSource GCVE Database
Not known to be exploited · fixed in 5.15.0-1117.124~20.04.1 : update Linux kernel when convenient.
Data as of 28 Oct 2026, 01:00 UTC
Rated by Threat Radar · CVSS not yet scored by NVD
- Patch
- Available – fixed in 5.15.0-1117.124~20.04.1, 5.15.0-1123.132~20.04.1, 5.15.0-1122.131~20.04.1 +27
Exploitation evidence
Disclosed: evidence found.
CVE published 22 Aug 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 26 Oct 2026.
What to do
Upgrade to a fixed release listed under Affected software.
Patches and advisories
Affected software
| Product | Affected | Fixed in |
|---|---|---|
Ubuntu 26.04 LTSlinuxpkg:deb/ubuntu/linux?arch=source&distro=resoluteOther threats | Affected
| Fixed in– |
Ubuntu 26.04 LTSlinux-awspkg:deb/ubuntu/linux-aws?arch=source&distro=resoluteOther threats | Affected
| Fixed in– |
Ubuntu 26.04 LTSlinux-azurepkg:deb/ubuntu/linux-azure?arch=source&distro=resoluteOther threats | Affected
| Fixed in– |
Ubuntu 26.04 LTSlinux-azure-fdepkg:deb/ubuntu/linux-azure-fde?arch=source&distro=resoluteOther threats | Affected
| Fixed in– |
Ubuntu 26.04 LTSlinux-gcppkg:deb/ubuntu/linux-gcp?arch=source&distro=resoluteOther threats | Affected
| Fixed in– |
Ubuntu 26.04 LTSlinux-gkepkg:deb/ubuntu/linux-gke?arch=source&distro=resoluteOther threats | Affected
| Fixed in– |
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
Description
In the Linux kernel, the following vulnerability has been resolved: usb: atm: cxacru: properly kill rcv_urb on error in cxacru_cm() If cxacru_cm() encounters an error while submitting or waiting for snd_urb, it aborts and returns the error without killing the already submitted rcv_urb. This leaves the rcv_urb active. When this happens during initialization (e.g., in cxacru_atm_start()), the driver may ignore the error and proceed to call cxacru_poll_status(), which invokes cxacru_cm() again. Attempting to submit the still-active rcv_urb triggers a warning in usb_submit_urb(): cxacru 1-1:1.0: send of cm 0x84 failed (-104) ATM dev 0: cxacru_atm_start: CHIP_ADSL_LINE_START returned -104 ------------[ cut here ]------------ URB ffff88812658d200 submitted while active WARNING: drivers/usb/core/urb.c:379 at usb_submit_urb+0x79/0x18b0 drivers/usb/core/urb.c:379 ... Call Trace: <TASK> cxacru_cm+0x21a/0xf10 drivers/usb/atm/cxacru.c:631 cxacru_cm_get_array drivers/usb/atm/cxacru.c:722 [inline] cxacru_poll_status+0x178/0x1110 drivers/usb/atm/cxacru.c:828 cxacru_atm_start+0x185/0x360 drivers/usb/atm/cxacru.c:814 usbatm_atm_init+0x144/0x3a0 drivers/usb/atm/usbatm.c:927 usbatm_usb_probe+0x15cb/0x1db0 drivers/usb/atm/usbatm.c:1178 cxacru_usb_probe+0x17f/0x220 drivers/usb/atm/cxacru.c:1370 ... To fix this, ensure that rcv_urb is properly killed if cxacru_cm() aborts early. We can safely call usb_kill_urb() on rcv_urb in the error path, as it is safe to call even if the URB is not active (e.g., if it failed to submit in the first place, or if it already completed).
References
- ubuntu.com/security/CVE-2026-74680 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2026-74680 (opens in a new tab)
- git.kernel.org/linus/c2f811314be351d86b6ab41e9297ae80d8da6f86 (opens in a new tab)
- ubuntu.com/security/notices/USN-8878-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8879-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8877-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8875-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8875-2 (opens in a new tab)