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PatchSiren cyber security CVE debrief

CVE-2026-74580 Linux CVE debrief

The Linux kernel has a vulnerability that has been resolved, affecting the vhost component. The vulnerability involves the improper resetting of the vring metadata cache during vring reconfiguration, which can lead to memory access outside the region the IOTLB actually maps. This issue arises when VHOST_SET_VRING_ADDR replaces vq->desc, vq->avail, and vq->used, or when VHOST_SET_VRING_NUM changes the region sizes. The vulnerability has a high defensive priority due to its potential impact on system security. System administrators and users of the Linux kernel should verify their systems and apply the patch or update to the latest version. The cache is not reset when VHOST_SET_VRING_ADDR replaces vq->desc, vq->avail and vq->used, nor when VHOST_SET_VRING_NUM changes the region sizes. This can lead to memory access outside the region the IOTLB actually maps. The vulnerability has been resolved in the Linux kernel.

Vendor
Linux
Product
Unknown
CVSS
Unknown
CISA KEV
Not listed in stored evidence
Original CVE published
2026-08-21
Original CVE updated
2026-08-21
Advisory published
2026-08-21
Advisory updated
2026-08-21

Who should care

System administrators and users of the Linux kernel should be aware of this vulnerability and take steps to mitigate it. They should verify their systems and apply the patch or update to the latest version. The vulnerability has a high defensive priority due to its potential impact on system security. Security teams and vulnerability management teams should also be aware of this vulnerability and review their systems for potential exposure.

Technical summary

The Linux kernel has a vulnerability that has been resolved. The vhost: reset the vring metadata cache on vring reconfiguration. The cache is not reset when VHOST_SET_VRING_ADDR replaces vq->desc, vq->avail and vq->used, nor when VHOST_SET_VRING_NUM changes the region sizes. This can lead to memory access outside the region the IOTLB actually maps. The vulnerability has a high defensive priority due to its potential impact on system security.

Defensive priority

This vulnerability has a high defensive priority due to its potential impact on system security.

Recommended defensive actions

  • Update the Linux kernel to the latest version
  • Apply the patch for the vhost: reset the vring metadata cache on vring reconfiguration
  • Monitor system logs for potential attacks
  • Review compensating controls for exposed systems while remediation is scheduled and verified
  • Check relevant monitoring, detection, and logs for exposed assets that need extra review
  • Track exceptions, retest remediated assets, and close the item only after evidence is documented
  • Confirm whether affected product deployments exist in managed environments and assign an owner for follow-up

Evidence notes

The evidence for this vulnerability is based on the Linux kernel source code and the NVD database. The vulnerability has been resolved in the Linux kernel. The vhost: reset the vring metadata cache on vring reconfiguration. The cache is not reset when VHOST_SET_VRING_ADDR replaces vq->desc, vq->avail and vq->used, nor when VHOST_SET_VRING_NUM changes the region sizes. This can lead to memory access outside the region the IOTLB actually maps. System administrators and users of the Linux kernel should verify their systems and apply the patch or update to the latest version. The NVD database provides additional information on the vulnerability.

Official resources

AI-assisted PatchSiren debrief based on the supplied source corpus. The CVE record was published on 2026-08-21T17:16:44.210Z and has not been modified since then.