Red Hat Security Advisory: kernel-rt security update
The kernel-rt packages provide the Real Time Linux Kernel, which enables fine-tuning for systems with extremely high determinism requirements. Security Fix(es): * kernel: vsock/virtio: Validate length in packet header before skb_put() (CVE-2025-39718) For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.
AI Analysis
Technical Summary
CVE-2025-39718 is a vulnerability in the Linux kernel packages used by Red Hat Enterprise Linux 8 and related products. The issue involves the vsock/virtio subsystem where the length in the packet header is not properly validated before the skb_put() function is called, which could lead to memory corruption (CWE-787). Red Hat has released a security update that fixes this by adding proper validation of the packet header length. The update requires a system reboot to be effective.
Potential Impact
The vulnerability could allow an attacker to cause memory corruption in the kernel via crafted vsock/virtio packets. This may lead to system instability or potentially escalate privileges depending on exploitation. Red Hat rates this issue as having moderate security impact.
Mitigation Recommendations
Red Hat has released an official security update for Red Hat Enterprise Linux 8 and related products that fixes this vulnerability. Users should apply the update as described in Red Hat advisory RHSA-2025:21398 and reboot affected systems to ensure the fix is applied. No additional mitigation steps are required beyond applying the official patch and rebooting.
Red Hat Security Advisory: kernel-rt security update
Description
The kernel-rt packages provide the Real Time Linux Kernel, which enables fine-tuning for systems with extremely high determinism requirements. Security Fix(es): * kernel: vsock/virtio: Validate length in packet header before skb_put() (CVE-2025-39718) For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.
Affected software
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Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2025-39718 is a vulnerability in the Linux kernel packages used by Red Hat Enterprise Linux 8 and related products. The issue involves the vsock/virtio subsystem where the length in the packet header is not properly validated before the skb_put() function is called, which could lead to memory corruption (CWE-787). Red Hat has released a security update that fixes this by adding proper validation of the packet header length. The update requires a system reboot to be effective.
Potential Impact
The vulnerability could allow an attacker to cause memory corruption in the kernel via crafted vsock/virtio packets. This may lead to system instability or potentially escalate privileges depending on exploitation. Red Hat rates this issue as having moderate security impact.
Mitigation Recommendations
Red Hat has released an official security update for Red Hat Enterprise Linux 8 and related products that fixes this vulnerability. Users should apply the update as described in Red Hat advisory RHSA-2025:21398 and reboot affected systems to ensure the fix is applied. No additional mitigation steps are required beyond applying the official patch and rebooting.
Technical Details
- Gcve Source
- db.gcve.eu
- Csaf Category
- csaf_security_advisory
- Csaf Version
- 2.0
- Publisher
- Red Hat Product Security
- Advisory Id
- RHSA-2025:21398
- Cve Count
- 1
- Additional Cves
- []
- Cvss Version
- null
Threat ID: 6a3da1dc4853345fc1829a25
Added to database: 06/25/2026, 21:47:08 UTC
Last enriched: 06/25/2026, 22:21:50 UTC
Last updated: 07/02/2026, 08:51:16 UTC
Views: 7
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