CVE-2026-31578: Linux kernel · media: as102: fix to not free memory after the device is registered in as102_usb_probe()
Affects Linux kernelSource GCVE Database
Not known to be exploited.
Data as of 12 Nov 2026, 00:34 UTC
Rated by Threat Radar · No CVSS score from NVD or the CNA
Thin evidence
One scorer or noneExploitation evidence
Disclosed: evidence found.
CVE published 24 Apr 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: 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 11 Nov 2026.
Description
In the Linux kernel, the following vulnerability has been resolved: media: as102: fix to not free memory after the device is registered in as102_usb_probe() In as102_usb driver, the following race condition occurs: ``` CPU0 CPU1 as102_usb_probe() kzalloc(); // alloc as102_dev_t .... usb_register_dev(); fd = sys_open("/path/to/dev"); // open as102 fd .... usb_deregister_dev(); .... kfree(); // free as102_dev_t .... sys_close(fd); as102_release() // UAF!! as102_usb_release() kfree(); // DFB!! ``` When a USB character device registered with usb_register_dev() is later unregistered (via usb_deregister_dev() or disconnect), the device node is removed so new open() calls fail. However, file descriptors that are already open do not go away immediately: they remain valid until the last reference is dropped and the driver's .release() is invoked. In as102, as102_usb_probe() calls usb_register_dev() and then, on an error path, does usb_deregister_dev() and frees as102_dev_t right away. If userspace raced a successful open() before the deregistration, that open FD will later hit as102_release() --> as102_usb_release() and access or free as102_dev_t again, occur a race to use-after-free and double-free vuln. The fix is to never kfree(as102_dev_t) directly once usb_register_dev() has succeeded. After deregistration, defer freeing memory to .release(). In other words, let release() perform the last kfree when the final open FD is closed.
References
- git.kernel.org/stable/c/0d36653a3a821e5a974798adb347b3ea09332914 (opens in a new tab)
- git.kernel.org/stable/c/25d500cf391e384356a612b85cf60b353ad3cd0c (opens in a new tab)
- git.kernel.org/stable/c/07ceb444c8f627cf863864d4274b5a77769725ed (opens in a new tab)
- git.kernel.org/stable/c/cb8092038e95dc1113a68e63762de40fff61ba71 (opens in a new tab)
- git.kernel.org/stable/c/582fbecb3756330006fe1950762412a68c2cacd2 (opens in a new tab)
- git.kernel.org/stable/c/09e9206008b887aa553733bd915d73131071a086 (opens in a new tab)
- git.kernel.org/stable/c/2eeae47a438694408189138048a786be99954032 (opens in a new tab)
- git.kernel.org/stable/c/7e5aedf6059cba2a669d86caeaf5a51f33ec85a1 (opens in a new tab)
- git.kernel.org/stable/c/8bd29dbe03fc5b0f039ab2395ff37b64236d2f0c (opens in a new tab)