VulnerabilityPublished 17 Sep 2026Updated 21 Oct 2026

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

Affects Linux kernelSource CVE Database V5

Not known to be exploited · fixed in bf9387488d6394845076928c6ca5315ce5d84f54 : update Linux kernel when convenient.

Data as of 26 Oct 2026, 13:47 UTC

Severity

Unrated

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.
Patch: Available – fixed in bf9387488d6394845076928c6ca5315ce5d84f54, a6e4b9a6deb9362ef7a0706c70d674e92fe1411a, 53a5b262d706b572840cbe8feae392538077ee19 +1

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

Upgrade Linux kernel to bf9387488d6394845076928c6ca5315ce5d84f54, a6e4b9a6deb9362ef7a0706c70d674e92fe1411a, 53a5b262d706b572840cbe8feae392538077ee19 or 8ba0d143e471c85f8a116707c0b42bf046b0a7b3.

Affected software

Product	Affected	Fixed in
LinuxLinux	Affected ≥ 48eb03dd26304c24f03bdbb9382e89c8564e71df, < bf9387488d6394845076928c6ca5315ce5d84f54	Fixed in bf9387488d6394845076928c6ca5315ce5d84f54
LinuxLinux	Affected ≥ 48eb03dd26304c24f03bdbb9382e89c8564e71df, < a6e4b9a6deb9362ef7a0706c70d674e92fe1411a	Fixed in a6e4b9a6deb9362ef7a0706c70d674e92fe1411a
LinuxLinux	Affected ≥ 48eb03dd26304c24f03bdbb9382e89c8564e71df, < 53a5b262d706b572840cbe8feae392538077ee19	Fixed in 53a5b262d706b572840cbe8feae392538077ee19
LinuxLinux	Affected ≥ 48eb03dd26304c24f03bdbb9382e89c8564e71df, < 8ba0d143e471c85f8a116707c0b42bf046b0a7b3	Fixed in 8ba0d143e471c85f8a116707c0b42bf046b0a7b3
LinuxLinux	Affected =6.8	Fixed in–

Description

In the Linux kernel, the following vulnerability has been resolved: xsk: honor XDP_TX_METADATA in zero-copy path The zero-copy path reads TX metadata whenever the UMEM has metadata space, even if the descriptor does not set XDP_TX_METADATA. Pass descriptor options through the metadata helpers and ignore metadata unless the option is set. This does not fix the existing per-WQE metadata handling for mlx5 MPWQEs. Only the descriptor that starts a session passes through xsk_tx_metadata_request() and configures offload state shared by the batch. Metadata on descriptors joining an open session is therefore not validated and does not configure its requested offloads. In addition, a non-NULL metadata pointer from such a descriptor is treated as a timestamp completion request even when XDP_TXMD_FLAGS_TIMESTAMP is not set, so its metadata union can be overwritten with an unrequested timestamp. Fixing mixed metadata states within one MPWQE requires a separate change.

References

Community reviews

Loading reviews…