Vulnerability in Linux kernel (CVE-2026-98484)
Summary
Vulnerability in Linux kernel (CVE-2026-98484). 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:
netfilter: nf_tables: skip expired catchall elements on insert and delete
nft_setelem_catchall_insert() looks up duplicates with
nft_set_elem_active() only, while nft_set_catchall_lookup() and the
dump path additionally skip expired elements.
Once a catchall element with a timeout expires, this predicate drift
makes it invisible to userspace dumps, yet it still blocks
re-insertion: with NLM_F_EXCL the request fails with -EEXIST, and
without it the request reports success but silently inserts nothing.
The stale entry only goes away when the (user-tunable) gc interval
elapses, so the catchall rule may silently stop matching for an
arbitrarily long time after its first expiration.
The delete path shows the same drift: nft_setelem_catchall_deactivate()
picks the first active-next entry in the catchall list, so with an
expired entry still pending GC it retires the stale entry instead of
the fresh one, and it deactivates an element that userspace no longer
sees instead of failing with -ENOENT.
Align both walks with the lookup and dump predicates: only an element
that is active and not expired counts as a duplicate or delete
candidate, using the per-netns timestamp taken at transaction start,
in line with the set backend .insert/.deactivate and catchall GC sync
paths.
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-2026-98484 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-2026-98484" on the vendor's site.
CVE-2026-98484 (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-2026-98484 linux
References
- web git.kernel.org
- web git.kernel.org
- web git.kernel.org
- web git.kernel.org
- web nvd.nist.gov
- web github.com