Vulnerability in Linux kernel (CVE-2026-89971)
Summary
Vulnerability in Linux kernel (CVE-2026-89971). 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:
nvme: skip the zoned limits update if the zone info query failed
nvme_query_zone_info() returns either a negative errno or a positive
NVMe status code, but nvme_update_ns_info_block() only tests for the
negative case:
ret = nvme_query_zone_info(ns, lbaf, &zi);
if (ret < 0)
goto out;
If the device fails the Identify Namespace (I/O Command Set specific)
command, or the Identify Controller command issued by
nvme_set_max_append(), the positive status falls through and setup
continues with the zero-initialized zone info. nvme_update_zone_info()
then marks the queue zoned with chunk_sectors and ns->head->zsze set to
zero.
blk_validate_zoned_limits() does not check chunk_sectors, so the limits
commit succeeds. blk_revalidate_disk_zones() does reject the zero zone
size, but by then the limits are live and nothing rolls them back, so
I/O keeps being submitted to a zoned queue with a zero zone size and
disk_zone_no() shifts by ilog2(0):
nvme0n1: Invalid non power of two zone size (0)
UBSAN: shift-out-of-bounds in include/linux/blkdev.h:747:16
shift exponent -1 is negative
disk_zone_no include/linux/blkdev.h:747 [inline]
bio_straddles_zones include/linux/blkdev.h:1058 [inline]
blk_zone_wplug_handle_write block/blk-zoned.c:1423 [inline]
blk_zone_plug_bio.cold+0x25/0x1c8 block/blk-zoned.c:1605
blk_mq_submit_bio+0x18fb/0x2870 block/blk-mq.c:3196
submit_bh_wbc+0x575/0x740 fs/buffer.c:2824…
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-2026-89971 has been found in Linux kernel.
Risk of unauthorized operations or information disclosure. CVSS score: 7.5/10.
What to do: apply the vendor's official patched release.
If unsure, ask your IT team or search "Linux kernel CVE-2026-89971" on the vendor's site.
CVE-2026-89971 (Linux kernel) — CVSS v3 7.5
Attack vector: remote (network-reachable) / unauthenticated / no user interaction
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: High (CVSS 7.5/10). 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。
Affected packages
Fix status by distribution
Fixed packages published by each distribution for this CVE
- Debian DEBIAN-CVE-2026-89971 linux Fixed in: 6.12.113-1
- Ubuntu UBUNTU-CVE-2026-89971 linux-hwe-edge
References
- advisory nvd.nist.gov
- advisory github.com
- package git.kernel.org
- web git.kernel.org
- web git.kernel.org
- web git.kernel.org
- web git.kernel.org
- web github.com