Vulnerability in Linux kernel (CVE-2026-90090)
Summary
Vulnerability in Linux kernel (CVE-2026-90090). 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:
Bluetooth: btmtksdio: Fix out-of-bounds DMA read in the TX path
btmtksdio_tx_packet() rounds the transfer size up to the SDIO block size
of 256 bytes, but hands the host controller the SKB buffer as is:
err = sdio_writesb(bdev->func, MTK_REG_CTDR, skb->data,
round_up(skb->len, MTK_SDIO_BLOCK_SIZE));
Only skb->len bytes hold packet data, so the controller reads up to 255
bytes of uninitialised memory and sends it to the device over the SDIO
bus. Depending on how much tailroom slack the SKB allocation happens to
carry, that read can also extend past the end of the buffer.
Compute the padded length up front, ensure the SKB has tailroom for it,
and zero-fill the padding with skb_put_zero(). skb->len then covers the
padding, so sdio_writesb() no longer needs to round up. byte_tx keeps
counting the header and the payload only, and the error path restores the
SKB so that the caller can requeue it.
Writing behind skb->tail is only safe because the driver owns the buffer,
which "Bluetooth: btmtksdio: Take exclusive ownership of the SKB before
TX" ensures.
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-2026-90090 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-2026-90090" on the vendor's site.
CVE-2026-90090 (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。
References
- web git.kernel.org
- web git.kernel.org
- web git.kernel.org
- web git.kernel.org
- web git.kernel.org
- web git.kernel.org
- web nvd.nist.gov
- web github.com