CVE-2026-45949: Linux kernel · hwrng: core – use RCU and work_struct to fix race condition
Affects Linux kernelSource GCVE Database
Not known to be exploited · CVSS 4.7 Medium.
Data as of 26 Oct 2026, 17:16 UTC
- EPSS
- 0.08% chance of exploitation in 30 days – higher than 0% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:HExploitation evidence
Disclosed: evidence found.
CVE published 27 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 LTSlinux-azure-fdepkg:deb/ubuntu/linux-azure-fde@7.0.0-1008.8?arch=source&distro=resoluteOther threats | Affected
| Fixed in– |
Ubuntu 25.10linuxpkg:deb/ubuntu/linux?arch=source&distro=questingOther threats | Affected
| Fixed in– |
Ubuntu 25.10linux-awspkg:deb/ubuntu/linux-aws?arch=source&distro=questingOther threats | Affected
| Fixed in– |
Ubuntu 25.10linux-azurepkg:deb/ubuntu/linux-azure?arch=source&distro=questingOther threats | Affected
| Fixed in– |
Ubuntu 25.10linux-azure-fdepkg:deb/ubuntu/linux-azure-fde?arch=source&distro=questingOther threats | Affected
| Fixed in– |
Ubuntu 25.10linux-gcppkg:deb/ubuntu/linux-gcp?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
A fix for this vulnerability is available in the Linux kernel. Users should update to a patched kernel version that includes the fix for CVE-2026-45949. Since this is a kernel-level issue, applying the official kernel update from the vendor or distribution is the recommended remediation. No additional mitigations are specified or required beyond applying the patch.
Description
CVE-2026-45949 is a race condition vulnerability in the Linux kernel's hardware random number generator (hwrng) core. The issue arises from improper synchronization around the hwrng_fill pointer and thread management, leading to use-after-free conditions. This can cause kernel instability or crashes. The vulnerability has been fixed by serializing thread start/stop operations with a mutex lock and converting certain references to use RCU and work_struct mechanisms to avoid deadlocks and use-after-free scenarios.