CVE-2026-46123: Linux kernel · Bluetooth: virtio_bt: clamp rx length before skb_put
Affects Linux kernelSource GCVE Database
Not known to be exploited · CVSS 7.7 High · patch available : patch Linux kernel soon.
Data as of 26 Oct 2026, 14:05 UTC
- EPSS
- 0.1% chance of exploitation in 30 days – higher than 3% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available
CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:HExploitation evidence
Disclosed: evidence found.
CVE published 28 May 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 26.04 LTSlinuxpkg:deb/ubuntu/linux@7.0.0-28.28?arch=source&distro=resoluteOther threats | Affected
| Fixed in– |
Ubuntu 26.04 LTSlinux-awspkg:deb/ubuntu/linux-aws@7.0.0-1008.8?arch=source&distro=resoluteOther threats | Affected
| Fixed in– |
Ubuntu 26.04 LTSlinux-azurepkg:deb/ubuntu/linux-azure@7.0.0-1009.9?arch=source&distro=resoluteOther threats | Affected
| Fixed in– |
Ubuntu 26.04 LTSlinux-azure-fdepkg:deb/ubuntu/linux-azure-fde@7.0.0-1008.8?arch=source&distro=resoluteOther threats | Affected
| Fixed in– |
Ubuntu 26.04 LTSlinux-gcppkg:deb/ubuntu/linux-gcp@7.0.0-1008.8?arch=source&distro=resoluteOther threats | Affected
| Fixed in– |
Ubuntu 26.04 LTSlinux-gkepkg:deb/ubuntu/linux-gke@7.0.0-1003.4?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.
AI-suggested
A patch is available and should be applied to affected Linux kernel versions. The vendor advisory from Ubuntu confirms that this issue has been fixed. Systems running affected versions should upgrade to a fixed kernel release to remediate this vulnerability.
Description
A vulnerability in the Linux kernel's Bluetooth virtio_bt driver allowed a malicious or buggy backend to cause the kernel to include uninitialized heap memory in received packets by reporting an invalid length. This could lead to information disclosure and denial of service. The issue was fixed by clamping the received length to the actual buffer size and rejecting zero-length packets. The vulnerability affects multiple specific Linux kernel versions and has a CVSS score of 7.7 (medium severity).
References
- ubuntu.com/security/CVE-2026-46123 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2026-46123 (opens in a new tab)
- git.kernel.org/linus/21bd244b6de5d2fe1063c23acc93fbdd2b20d112 (opens in a new tab)
- git.kernel.org/stable/c/21bd244b6de5d2fe1063c23acc93fbdd2b20d112 (opens in a new tab)
- git.kernel.org/stable/c/6c1730099a6fc18b183bd6c1adad3b54adcaeda9 (opens in a new tab)
- git.kernel.org/stable/c/b40cdd1b1370d76e9e760af4490cb4a351cceead (opens in a new tab)
- git.kernel.org/stable/c/e6b4296f170d949ebba937cf6a3f247ec9550d2c (opens in a new tab)
- git.kernel.org/stable/c/ed41c81d30b211a671667259c3b5feeba0e062d5 (opens in a new tab)
- ubuntu.com/security/notices/USN-8566-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8568-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8569-1 (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-8593-1 (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)