CVE-2026-74311 — virtio: rtc: tear down old virtqueues before restore
In the Linux kernel, the following vulnerability has been resolved: virtio: rtc: tear down old virtqueues before restore virtio_device_restore() resets the device and restores the negotiated features before calling ->restore(). viortc_freeze() intentionally leaves the existing virtqueues in place so the alarm queue can still wake the system, but viortc_restore() immediately calls viortc_init_vqs() without first deleting those old queues. If virtqueue reinitialization fails on virtio-pci, the transport error path can run vp_del_vqs() against a newly allocated vp_dev->vqs array while vdev->vqs still contains the old virtqueues. vp_del_vqs() then looks up queue state through the new array and can dereference a NULL info pointer in vp_del_vq(), crashing the guest kernel during restore. This can also happen during a non-faulty reinitialization, when one of the vp_find_vqs_msix() attempts is unsuccessful before a later attempt would succeed. Delete the stale virtqueues before rebuilding them. If restore fails before virtio_device_ready(), reuse the remove path to stop the device. Once the device is ready, return errors directly instead of deleting the virtqueues again.
Who exploits it and how urgent it is
A 0–100 score combining confirmed exploitation, ransomware and APT use, public exploits, EPSS and severity.
How the score was calculated
- EPSS 0.2% (30-day exploitation probability)+1
- Technical severity (high)+6
The score orders the patch queue; it does not replace your asset context (internet exposure, criticality, compensating controls).
Triage
Is it exploited, how likely is exploitation, what does it touch, and how severe do the sources call it.
Remediation
Fixes and mitigations documented by the sources — linked to the original advisory.
No fix documented by the sources we poll. That does not mean none exists: check the vendor advisory.
First 24 hours
Ordered from the record’s own fields — exposure first, because you cannot patch what you have not found. A rule-generated starting point.
- Identify exposed assets running the affected vendor/product/version combinations (Linux Linux).
- No fix documented in the sources: reduce exposure and monitor the vendor advisory.
- Search available logs for exploit probes, errors and authentication anomalies.
Affected scope
Vendor, product and versions as the sources word them.
| Vendor | Product | Versions | Status | Source |
|---|---|---|---|---|
| Linux | Linux | ≥ 0623c759276885c3ae88197ba6fb5c9c6ba8612f and < 79366023aa891ca31376021a7bccff6384ca1ff1≥ 0623c759276885c3ae88197ba6fb5c9c6ba8612f and < aebebd1e9d70b650fc9e877082e0134edcf511da≥ 0623c759276885c3ae88197ba6fb5c9c6ba8612f and < 548d2208455f14e6121404c6e30e997bfe0cd264version 6.16 | Vulnerable | CVE Program (cve.org) e CISA ADP |
Attack characteristics
The CVSS vector, decoded. It describes the attack, not your exposure to it.
Every base score collected
Sources score independently and may disagree; each row says who scored it and under which version.
| Score | Version | Severity | Expl. | Impact | Scored by |
|---|---|---|---|---|---|
| 7.8 | CVSS 3.1 | High | 1.8 | 5.9 | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 via NIST National Vulnerability Database |
| 7.8 | CVSS 3.1 | High | — | — | Linux via CVE Program (cve.org) e CISA ADP |
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H (score shown at the top: 416baaa9-dc9f-4396-8d5f-8c081fb06d67) Detection
Read off the CVSS vector and the weakness class. Starting points, not tested rules.
- Local/physical vector: focus on endpoint telemetry (EDR) from affected hosts.
Timeline
What happened to this CVE, newest first.
- 2026
- Affected products added · linux/linux
- Record published
- CVSS changed · 7.8
- Source status changed · → Received
- Record created in this database
- CVE published
Source activity
Repeated readings are counted rather than listed.
- 1× Official description updated · Oct 15, 2026 – Oct 15, 2026
References
3 on the record
Elsewhere on this site
Related CVEs (same products)
- Critical CVE-2026-99999 ipv4: validate checksum_start before completing checksum 16h
- Unknown CVE-2026-98432 ipv4: free inet_opt and ireq_opt after an RCU grace period 16h
- Unknown CVE-2026-98431 RDMA/uverbs: Fix mmap_lock/disassociation_lock circular dependency 1d
- Unknown CVE-2026-98430 RDMA/efa: Keep admin queues alive while IRQ is registered 1d
- Unknown CVE-2026-98429 RDMA/efa: Keep EQ resources alive while IRQ is registered 1d
- Unknown CVE-2026-98428 ALSA: usb: 6fire: Avoid embedded URBs 1d
Not in any source we poll
Listed rather than left blank: an empty field and an unmeasured one look identical on screen, and only one is a reason to look elsewhere.
- No fixed version, patch or mitigation documented.
- No CISA SSVC assessment.
- No CWE classification.
- No confirmed IOCs, IP addresses, domains, file hashes, or malware artifacts supplied.
- No organization-specific asset inventory, compensating-control status, or patch deployment evidence supplied.
- No exploit packet captures, log samples, or incident case IDs supplied.
Answered from this record
Text assembled only from the fields above — no additional claims.
What should defenders know first?
CVE-2026-74311 is "virtio: rtc: tear down old virtqueues before restore", rated High. It affects Linux (Linux); versions are in the scope table. It is not in CISA KEV, which does not rule out exploitation. CVSS 7.8 describes technical severity. EPSS 0.17% estimates the probability of exploitation in 30 days; neither replaces your asset context. First verify whether exposed or business-critical assets run the affected versions, apply vendor fixes or mitigations, and preserve logs for review.
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