CVE-2026-99286: Linux kernel · xen-netback: Fix XenBus connection failure cleanup
Affects Linux kernelSource GCVE Database
Not known to be exploited.
Data as of 13 Nov 2026, 14:18 UTC
Rated by Threat Radar · CVSS not yet scored by NVD
Thin evidence
One scorer or noneExploitation evidence
Disclosed: evidence found.
CVE published 10 Nov 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 13 Nov 2026.
What to do
Affected software
| Product | Affected | Fixed in |
|---|---|---|
Ubuntu 26.10linuxpkg:deb/ubuntu/linux?arch=source&distro=stonkingOther threats | Affected
| Fixed in– |
Ubuntu 26.10linux-awspkg:deb/ubuntu/linux-aws?arch=source&distro=stonkingOther threats | Affected
| Fixed in– |
Ubuntu 26.10linux-azurepkg:deb/ubuntu/linux-azure?arch=source&distro=stonkingOther threats | Affected
| Fixed in– |
Ubuntu 26.10linux-azure-fdepkg:deb/ubuntu/linux-azure-fde?arch=source&distro=stonkingOther threats | Affected
| Fixed in– |
Ubuntu 26.10linux-gcppkg:deb/ubuntu/linux-gcp?arch=source&distro=stonkingOther threats | Affected
| Fixed in– |
Ubuntu 26.10linux-oraclepkg:deb/ubuntu/linux-oracle?arch=source&distro=stonkingOther threats | Affected
| Fixed in– |
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
AI-suggested
A fix for this vulnerability has been implemented in the Linux kernel. Users should update to patched kernel versions that include the fix for XSA-531. Since this is not a cloud service, manual patching or upgrading the affected Linux kernel versions is required.
Description
A vulnerability in the Linux kernel's xen-netback component related to XenBus connection failure cleanup has been fixed. The issue involves improper handling of vif->num_queues under rcu_read_lock, which could lead to readers accessing invalid queues. The fix ensures that vif->num_queues is unpublished before synchronize_net to prevent this condition. This vulnerability is tracked as XSA-531.
References
- ubuntu.com/security/CVE-2026-99286 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2026-99286 (opens in a new tab)
- git.kernel.org/stable/c/a97aa838903d15f865d80809f5198ff459c6634a (opens in a new tab)
- git.kernel.org/stable/c/07aca7d25ce8578fedde49855983a01c537a782b (opens in a new tab)
- git.kernel.org/stable/c/ade3082dcdee17c5767069883936d64ff83f6c9f (opens in a new tab)