Red Hat Security Advisory: kernel-rt security update
Affects Linux kernelSource GCVE Database
Not known to be exploited.
Data as of 5 Nov 2026, 19:32 UTC
Rated by Threat Radar · No CVSS score from NVD or the CNA
Exploitation evidence
Disclosed: evidence found.
CVE published 17 Nov 2025
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 5 Nov 2026.
What to do
AI-suggested
Red Hat has released updated kernel-rt packages that fix this vulnerability. Users of affected Red Hat Enterprise Linux 8 Real Time variants should apply the security update as detailed in Red Hat advisory RHSA-2025:21397 and reboot their systems to ensure the fix takes effect. No additional mitigation steps are required beyond applying the official update and rebooting.
Description
A security update for the Red Hat Real Time Linux Kernel (kernel-rt) addresses a vulnerability identified as CVE-2025-39718. The flaw involves improper validation of the length in the packet header before the skb_put() function call in the vsock/virtio kernel component. This issue could potentially lead to memory corruption or related impacts. Red Hat has rated this vulnerability as having moderate severity and has released updated kernel-rt packages for Red Hat Enterprise Linux 8 Real Time variants. A system reboot is required to apply the update.