CVE-2026-64457: linux

CVSS: UnknownReceived
AliasesUBUNTU-CVE-2026-64457DEBIAN-CVE-2026-64457
Published 25-07-2026Last modified 17-08-2026
Open JSON

Vulnerability summary

CVE-2026-64457 is a vulnerability in linux with no CVSS score yet. EPSS estimates a 0.21% chance of exploitation in the next 30 days, higher than 10.4% of scored vulnerabilities.

Overall risk
0/100
0100
Minimal · default modelHow is this calculated?
CVSS score
Not scored
010
No CVSS score recorded
EPSS score
0.21%
0%100%
Low · +0.03 pp in 30 days
KEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded

Advisory lineage

Upstream 0 · Downstream 17 · Related 17
OPENSUSE-SU-2026:11476-1OPENSUSE-SU-2026:22091-1SUSE-SU-2026:24179-1SUSE-SU-2026:24184-1SUSE-SU-2026:24197-1SUSE-SU-2026:24235-1

Timeline

  1. 25-07-2026
    PublishedVulnerability first disclosed.
  2. 17-08-2026
    Last modifiedVulnerability information updated.

Description

In the Linux kernel, the following vulnerability has been resolved: virtio_pci: fix vq info pointer lookup via wrong index Unbinding a virtio balloon device: echo virtio0 > /sys/bus/virtio/drivers/virtio_balloon/unbind triggers a NULL pointer dereference. The dmesg says: BUG: kernel NULL pointer dereference, address: 0000000000000008 [...] RIP: 0010:__list_del_entry_valid_or_report+0x5/0xf0 Call Trace: <TASK> vp_del_vqs+0x121/0x230 remove_common+0x135/0x150 virtballoon_remove+0xee/0x100 virtio_dev_remove+0x3b/0x80 device_release_driver_internal+0x187/0x2c0 unbind_store+0xb9/0xe0 kernfs_fop_write_iter.llvm.11660790530567441834+0xf6/0x180 vfs_write+0x2a9/0x3b0 ksys_write+0x5c/0xd0 do_syscall_64+0x54/0x230 entry_SYSCALL_64_after_hwframe+0x29/0x31 [...] </TASK> The virtio_balloon device registers 5 queues (inflate, deflate, stats, free_page, reporting) but only the first two are unconditional. The stats, free_page and reporting queues are each conditional on their respective feature bits. When any of these features are absent, the corresponding vqs_info entry has name == NULL, creating holes in the array. The root cause is an indexing mismatch introduced when vq info storage was changed to be passed as an argument. vp_find_vqs_msix() and vp_find_vqs_intx() store the info pointer at vp_dev->vqs[i], where 'i' is the caller's sparse array index. However, the virtqueue itself gets vq->index assigned from queue_idx, a dense index that skips NULL entries. When holes exist, 'i' and queue_idx diverge. Later, vp_del_vqs() looks up info via vp_dev->vqs[vq->index] using the dense index into the sparsely-populated array, and hits NULL. Fix this by storing info at vp_dev->vqs[queue_idx] instead of vp_dev->vqs[i], so the store index matches the lookup index (vq->index). Apply the fix to both the MSIX and INTX paths.

CVSS metrics

Risk metrics not yet published.

EPSS trend

Probability

0.21%

Chance of exploitation in the next 30 days

Percentile

10%

Versus all other CVEs

30-day change

+0.03 pp

From 0.18% on 21-09-2026

21-09-202621-10-2026
EPSS score
0.21%

Known exploited

Compare KEV catalogs

Not in any of the 3 tracked catalogs.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

No weakness data has been published for this record.

Affected systems

Ubuntu119 products
  • linux< 7.0.0-31.31
  • linux-allwinner-5.19All versions (No fix recorded)
  • linux-aws< 7.0.0-1012.12
  • linux-aws-5.0All versions (No fix recorded)
  • linux-aws-5.11All versions (No fix recorded)
Debian2 products
  • linux< 6.12.96-1 | < 7.1.4-1
  • linux-6.12< 6.12.100-1~deb12u1
Linux1 product
  • linux≥ 89a1c435aec269d109ed46ca7bbb10fa8edf7ace, < 41e6dc1a10036c9f47057033f19af7e52ec464b6 | ≥ 89a1c435aec269d109ed46ca7bbb10fa8edf7ace, < 075bc3c779e1ea7294afabdcb7e0a49536959b28 | ≥ 89a1c435aec269d109ed46ca7bbb10fa8edf7ace, < 64a4c0befa77bcc01076aec9f93863ffd4ed06b7 | ≥ 89a1c435aec269d109ed46ca7bbb10fa8edf7ace, < f7d380fb525c13bdd114369a1979c80c346e6abc | 6.11

3 vendors · 122 products

References

19 links
Show all 19 references