CVE-2026-23307: Linux kernel · can: ems_usb: ems_usb_read_bulk_callback(): check the proper length of a message
Affects Linux kernelSource GCVE Database
Not known to be exploited · CVSS 5.5 Medium · patch available : update Linux kernel when convenient.
Data as of 26 Oct 2026, 14:05 UTC
- EPSS
- 0.1% chance of exploitation in 30 days – higher than 2% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:HExploitation evidence
Disclosed: evidence found.
CVE published 25 Mar 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
Affected software
| Product | Affected | Fixed in |
|---|---|---|
Ubuntu 25.10linuxpkg:deb/ubuntu/linux@6.17.0-40.40?arch=source&distro=questingOther threats | Affected
| Fixed in– |
Ubuntu 25.10linux-awspkg:deb/ubuntu/linux-aws@6.17.0-1019.19?arch=source&distro=questingOther threats | Affected
| Fixed in– |
Ubuntu 25.10linux-azurepkg:deb/ubuntu/linux-azure@6.17.0-1020.20?arch=source&distro=questingOther threats | Affected
| Fixed in– |
Ubuntu 25.10linux-azure-fdepkg:deb/ubuntu/linux-azure-fde@6.17.0-1017.17?arch=source&distro=questingOther threats | Affected
| Fixed in– |
Ubuntu 25.10linux-gcppkg:deb/ubuntu/linux-gcp@6.17.0-1020.22?arch=source&distro=questingOther threats | Affected
| Fixed in– |
Ubuntu 25.10linux-oraclepkg:deb/ubuntu/linux-oracle@6.17.0-1018.18?arch=source&distro=questingOther threats | Affected
| Fixed in– |
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
AI-suggested
An official patch is available and should be applied to affected Linux kernel versions. Users should update their systems to the fixed kernel releases as provided by their distribution vendors. No additional mitigation steps are indicated by the vendor advisory.
Description
A vulnerability in the Linux kernel's can: ems_usb driver was resolved. The issue involved improper length checks in the ems_usb_read_bulk_callback() function, where the actual_length from a USB urb was confused with transfer_buffer_length, potentially leading to buffer overflow during message parsing. This flaw was fixed by adding proper size checks at both the start and end of message parsing to prevent overflow. The vulnerability affects specific Linux kernel versions listed and has a medium severity with a CVSS score of 5.5. A patch is available to address this issue.
References
- ubuntu.com/security/CVE-2026-23307 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2026-23307 (opens in a new tab)
- git.kernel.org/linus/38a01c9700b0dcafe97dfa9dc7531bf4a245deff (opens in a new tab)
- git.kernel.org/stable/c/1818974e1b5ef200e27f144c8cb8a246420bb54d (opens in a new tab)
- git.kernel.org/stable/c/18f75b9cbdc3703f15965425ab69dee509b07785 (opens in a new tab)
- git.kernel.org/stable/c/1cf469026d4a2308eaa91d04dca4a900d07a5c2e (opens in a new tab)
- git.kernel.org/stable/c/2833e13e2b099546abf5d40a483b4eb04ddd1f7b (opens in a new tab)
- git.kernel.org/stable/c/38a01c9700b0dcafe97dfa9dc7531bf4a245deff (opens in a new tab)
- git.kernel.org/stable/c/c703bbf8e9b4947e111c88d2ed09236a6772a471 (opens in a new tab)
- ubuntu.com/security/notices/USN-8567-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8574-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8575-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8576-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8574-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-8595-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8596-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8575-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-8576-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-8597-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8595-2 (opens in a new tab)