VulnerabilityPublished 17 Sep 2026Updated 5 Oct 2026

CVE-2026-90086: Linux kernel · xsk: honor XDP_TX_METADATA in zero-copy path

Affects Linux kernelSource GCVE Database

Authoritative record:CVE-2026-90086

Not known to be exploited.

Data as of 26 Oct 2026, 14:05 UTC

Severity

Medium

Rated by Threat Radar · CVSS not yet scored by NVD

EPSS: 0.2% chance of exploitation in 30 days – higher than 10% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.

Exploitation evidence

Disclosed: evidence found.
CVE published 17 Sep 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: 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 26 Oct 2026.

Disclosed: The CVE record is public on cve.org. Its publication is t = 0.
Detectable: A public nuclei template can find exposed instances, for defenders and attackers alike.
Weaponised: Public exploit code exists in Metasploit or Exploit-DB, or CISA SSVC or the CVSS exploit maturity reports a public proof of concept.
Exploited in the wild: CISA KEV lists it, CISA SSVC rates exploitation active, or a source reports attacks.
Observed by OffSeq Mirage: OffSeq Mirage honeypot sensors recorded attack traffic for this CVE, or found exposed hosts without attack traffic.

Moments are spaced evenly, not to scale; a dashed line marks a gap of six months or more. Deltas count from t = 0. Sources that give only a date (CISA KEV, Exploit-DB, or a time of exactly 00:00Z) read “same day” rather than hours. Metasploit modules carry the flaw’s disclosure date, not their release date, and nuclei templates carry no date, so both appear above but not on the timeline.

What to do

Affected software

Product	Affected	Fixed in
Ubuntu 26.04 LTSlinux`pkg:deb/ubuntu/linux?arch=source&distro=resolute`Other threats	Affected 6.17.0-5.5 – 7.0.0-38.38 23 affected builds	Fixed in–
Ubuntu 26.04 LTSlinux-aws`pkg:deb/ubuntu/linux-aws?arch=source&distro=resolute`Other threats	Affected 6.17.0-1002.2 – 7.0.0-1014.14 15 affected builds	Fixed in–
Ubuntu 26.04 LTSlinux-azure`pkg:deb/ubuntu/linux-azure?arch=source&distro=resolute`Other threats	Affected 6.17.0-1003.3 – 7.0.0-1017.17 15 affected builds	Fixed in–
Ubuntu 26.04 LTSlinux-azure-fde`pkg:deb/ubuntu/linux-azure-fde?arch=source&distro=resolute`Other threats	Affected 7.0.0-1003.3 – 7.0.0-1016.16 9 affected builds	Fixed in–
Ubuntu 26.04 LTSlinux-gcp`pkg:deb/ubuntu/linux-gcp?arch=source&distro=resolute`Other threats	Affected 6.17.0-1002.2 – 7.0.0-1014.14 13 affected builds	Fixed in–
Ubuntu 26.04 LTSlinux-gke`pkg:deb/ubuntu/linux-gke?arch=source&distro=resolute`Other threats	Affected 7.0.0-1002.3 – 7.0.0-1008.9 6 affected builds	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 has been applied to the Linux kernel to address this vulnerability. Users should update to patched kernel versions to remediate the issue. Since this is a kernel-level fix, applying the official kernel updates from the vendor or distribution is the recommended remediation.

Description

A vulnerability in the Linux kernel's xsk zero-copy path handling of XDP_TX_METADATA has been resolved. The issue involves improper reading and validation of TX metadata in certain descriptors, which can lead to unrequested timestamp overwrites in metadata. This flaw affects specific Linux kernel versions used in various Ubuntu releases.

Impact

The vulnerability could cause incorrect handling of metadata in the zero-copy path of the Linux kernel's XDP implementation, potentially leading to unrequested timestamp overwrites. This could affect network packet processing behavior in affected kernel versions. There is no indication of active exploitation in the wild.

Summary

The Linux kernel vulnerability (CVE-2026-90086) concerns the xsk zero-copy path that reads TX metadata whenever the UMEM has metadata space, regardless of whether the descriptor sets XDP_TX_METADATA. The fix ensures descriptor options are passed through metadata helpers and metadata is ignored unless explicitly requested. However, existing per-WQE metadata handling for mlx5 MPWQEs remains unaddressed by this fix. Descriptors joining an open session do not have their metadata validated, and a non-NULL metadata pointer from such descriptors can be misinterpreted as a timestamp completion request, potentially overwriting metadata with an unrequested timestamp. A separate change is required to fix mixed metadata states within one MPWQE.

References

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Exploitation evidence

What to do

Affected software

Description

AI analysisMachine-generated, updated 24 Oct 2026, 21:23 UTC

Technical details

References

Community reviews

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