Vulnerability in Linux kernel (CVE-2026-98821)
Summary
Vulnerability in Linux kernel (CVE-2026-98821). 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:
block: reject polled dio with user integrity metadata
IOCB_HAS_METADATA leaves iocb->private as a uio_meta, while
iocb_bio_iopoll() expects a bio. Since 2729a60bbfb9, metadata I/O
always uses __blkdev_direct_IO(), which never publishes the bio for
polling, so IOPOLL calls bio_poll() on the uio_meta.
Reproducer: io_uring IOPOLL plus a PI attribute on an integrity device
(scsi_debug dif=1 dix=1). KASAN reports:
Oops: general protection fault, probably for non-canonical
address 0xdffffc0000000004
KASAN: null-ptr-deref in range
[0x0000000000000020-0x0000000000000027]
RIP: 0010:bio_poll+0x9d/0x4b0
Call Trace:
iocb_bio_iopoll+0x5b/0x80
io_uring_classic_poll+0xf3/0x140
io_do_iopoll+0x4e3/0xc00
io_iopoll_check+0x275/0x560
__do_sys_io_uring_enter+0x2e5/0x720
Return -EOPNOTSUPP when HIPRI is combined with user metadata.
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-2026-98821 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-2026-98821" on the vendor's site.
CVE-2026-98821 (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-2026-98821 linux Fixed in: 7.2.10-1
References
- web git.kernel.org
- web git.kernel.org
- web git.kernel.org
- web nvd.nist.gov
- web github.com