Vulnerability in Linux kernel (CVE-2026-90086)
Summary
Vulnerability in Linux kernel (CVE-2026-90086). Risk of unauthorized operations or information disclosure.
Original description
The description as published by the source.
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.
Source: NIST National Vulnerability Database NVD GitHub Advisory
Auto-generated summary
Assembled by SecPulse from the source data (CVSS, CWE, affected versions) using templates — no AI involved. Check the original description and references below for exact details.
A vulnerability tracked as CVE-2026-90086 has been found in Linux kernel.
Risk of unauthorized operations or information disclosure.
What to do: apply the vendor's official patched release.
If unsure, ask your IT team or search "Linux kernel CVE-2026-90086" on the vendor's site.
CVE-2026-90086 (Linux kernel)
Plan: 1) Audit SBOM/dependencies, 2) Stage→prod upgrade, 3) Add WAF/proxy monitoring on affected endpoints, 4) Hunt IOCs in logs.
Refs: see the GHSA / vendor advisory / patched release linked on this page.
A vulnerability (unclassified) exists in Linux kernel.
Check the vendor advisory for the affected versions of Linux kernel.
Severity: ?. Risk of unauthorized operations or information disclosure.
Update to the patched release per vendor advisory.
Until the patch is applied: disable the affected feature, apply WAF rules, or restrict access via network ACLs.
Search webserver/proxy logs for unusual request patterns matching this CVE's known IOCs. Audit SBOM/dependencies to find affected services.
Response actions
Concrete steps and command examples for SOC/SRE teams to execute in order
-
1Identify exposure identify
Audit SBOM/dependencies for affected components.資産台帳・SBOM・依存マニフェストで Linux kernel を使っているサービスとバージョンを洗い出す。
-
2Post-deployment verification verify
Confirm patched version is live in productionパッチ適用後、ステージングで PoC または同等の悪用パターンを再現して脆弱性が閉じたことを確認。本番ではアクセスログ・WAF でアラート再発が無いか継続監視。
Fix status by distribution
Fixed packages published by each distribution for this CVE
- Debian DEBIAN-CVE-2026-90086 linux
- Ubuntu UBUNTU-CVE-2026-90086 linux-hwe-edge
References
- web git.kernel.org
- web git.kernel.org
- web git.kernel.org
- web nvd.nist.gov
- web github.com