CVE-2026-97997

In the Linux kernel, the following vulnerability has been resolved: virtio_ring: fix stale descriptor flags after a failed packed add In a packed ring the AVAIL and USED bits sit i

Published Sep 25, 2026 · corrected/updated Oct 16, 2026 · evidence confidence high

In the Linux kernel, the following vulnerability has been resolved: virtio_ring: fix stale descriptor flags after a failed packed add In a packed ring the AVAIL and USED bits sit in the descriptor itself, so writing them makes that descriptor available. Those bit combinations flip meaning on every round of the ring, tracked by a wrap counter, so invalidating or validating a descriptor means inverting both bits. Commit 1ce9e6055fa0 ("virtio_ring: introduce packed ring support") has virtqueue_add_packed() make every descriptor of a chain available as it maps the chain, and write the head last. The device consumes the ring in order and stops at a head that is not available yet, so it never reaches the rest. When vring_map_one_sg() fails partway, unmap_release unmaps the segments and restores avail_used_flags, but the descriptors it wrote to in the ring stay marked with AVAIL and USED bits. The head is now the only entry that keeps the device from consuming these stale entries. For example, the ring would look like this now. Z - pre-previous command A - previous command B - aborted command C - current command [A1 DONE] [A2 DONE] [B2] [B3] [Z1 DONE] When the driver now attempts to issue the C command, the next add starts at the same head as B. If C spans less descriptors than B, there is no end marker because AVAIL and USED bits were still in place. And that means the device will start interpreting these stale entries (B2/B3) as another command entry, which then blocks the queue. This effect typically happens in swiotlb configurations under memory pressure, because vring_map_one_sg() can then fail with larger I/O requests which then leads to command abortions. There are broadly 2 ways to avoid leaving those flags behind: 1) Defer those flags too until the chain is complete. 2) Rewrite those flags for the previous wrap counter. Implement the second option in both packed add paths. The first option traverses the chain a second time on every successful add. The second optio

Grounded briefings

Catalog interpretations for three audiences. Each brief cites ingested metadata and the original advisories below. They are not independent research and they do not invent exploit steps.

Executive

CVE-2026-97997 is a unknown public vulnerability record for this product. It is not currently listed in the CISA Known Exploited catalog. Check the linked vendor or CERT advisories for patch status. This summary is a catalog interpretation of the ingested metadata and cites the original advisories below.

System administrator

Identify whether this product is in your estate, then compare installed versions with the affected ranges. Affected packages or ranges on record: linux (6.1.106-1, 6.1.106-2, 6.1.106-3); linux (6.12.100-1, 6.12.101-1, 6.12.105-1); linux (0 → 7.2.7-1). Check the linked vendor or CERT advisories for patch status. Prefer the vendor or distribution advisory linked in Sources before changing production systems. This is a catalog interpretation, not a runbook.

Security analyst

Signals on file: EPSS 0.2%. It is not currently listed in the CISA Known Exploited catalog. Sources contributing to this record: cve_org, epss, nvd, osv. Public exploit references, when present, are outbound links only and are not proof of active exploitation. This is a catalog interpretation of stored metadata.

Exploitation and remediation

Exploitation evidence
Not listed as known exploited in CISA KEV. Not in the CISA KEV catalog.
Patch and remediation
No required-action text is stored yet. Use the vendor or CERT links in Sources for patch availability.
Safe detection guidance
Compare installed versions with the affected ranges below and verify the advisory from the original publisher. This site stores metadata and outbound links only; it does not ship exploit code or proof-of-concept payloads.

Technology hubs

Debian

Code

The project this record applies to. Exploit listings stay in References.

Timeline

Detection, updates, and resolution for this record.

Sep 25, 2026 · NIST NVD
Detected
In the Linux kernel, the following vulnerability has been resolved: virtio_ring: fix stale descriptor flags after a failed packed add In a packed ring the AVAIL and USED bits sit in the descriptor itself, so writing them makes that descriptor available. Those bit combinations flip meaning on every round of the ring, tracked by a wrap counter, so invalidating or validating a descriptor means invert
Oct 15, 2026 · NIST NVD
Updated
In the Linux kernel, the following vulnerability has been resolved: virtio_ring: fix stale descriptor flags after a failed packed add In a packed ring the AVAIL and USED bits sit in the descriptor itself, so writing them makes that descriptor available. Those bit combinations flip meaning on every round of the ring, tracked by a wrap counter, so invalidating or validating a descriptor means invert
Oct 16, 2026 · OSV.dev
Fix available
linux fixed in 7.2.7-1
Oct 16, 2026 · OSV.dev
Fix available
linux fixed in 7.2.7-1
Oct 16, 2026 · OSV.dev
Updated
In the Linux kernel, the following vulnerability has been resolved: virtio_ring: fix stale descriptor flags after a failed packed add In a packed ring the AVAIL and USED bits sit in the descriptor itself, so writing them makes that descriptor available. Those bit combinations flip meaning on every round of the ring, tracked by a wrap counter, so invalidating or validating a descriptor means invert

Affected

Debian:12 linux6.1.106-1, 6.1.106-2, 6.1.106-3
Debian:13 linux6.12.100-1, 6.12.101-1, 6.12.105-1
Debian:14 linux0 → 7.2.7-1

Sources

CVE.orgVulnerability recordCVE-2026-97997
Official CVE identifier
cve.org
FIRST EPSSExploitation probabilityCVE-2026-97997
30-day exploitation probability 0.2%
first.org
NIST NVDVulnerability recordCVE-2026-97997
In the Linux kernel, the following vulnerability has been resolved: virtio_ring: fix stale descriptor flags after a failed packed add In a packed ring the AVAIL and USED bits sit in the descriptor itself, so writing them makes that descriptor available. Those bit combinations f
nvd.nist.gov
OSV.devPackage advisoryDEBIAN-CVE-2026-97997
osv.dev