Vulnerability in Linux kernel (CVE-2026-98548)
Summary
Vulnerability in Linux kernel (CVE-2026-98548). 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:
sctp: discard the rest of the packet on a stale-cookie error
When an association is in COOKIE-ECHOED state and the peer sends a
bundled [ERROR(Stale Cookie)][DATA] packet from one of its non-primary
addresses, processing the ERROR chunk takes the non-fatal stale-cookie
retry path sctp_sf_do_5_2_6_stale(), which queues
SCTP_CMD_DEL_NON_PRIMARY while keeping the association alive.
sctp_cmd_del_non_primary() removes every non-primary transport -
including the very transport this packet arrived on, which is still
referenced by the receive lookup and shared by all chunks of the
packet via chunk->transport.
sctp_assoc_rm_peer() does redirect asoc->peer.last_data_from away from
the removed transport, but right afterwards the bundled DATA chunk
makes sctp_assoc_bh_rcv() re-register
asoc->peer.last_data_from = chunk->transport unconditionally, undoing
the redirection with the just-removed transport.
Once the packet is done, the receive reference is dropped and the
transport is RCU-freed, while the surviving association keeps the
dangling last_data_from. A later FWD-TSN (or the delayed SACK timer)
makes sctp_gen_sack() dereference it (->param_flags and friends), and
sctp_make_sack()/sctp_outq_select_transport() may write to the freed
object and link it into the live transport list. This is a
use-after-free triggerable by any malicious SCTP peer (or a local
unprivileged user acting as one) with no capabilities req…
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-2026-98548 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-2026-98548" on the vendor's site.
CVE-2026-98548 (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-2026-98548 linux Fixed in: 6.1.190-1
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 git.kernel.org
- web git.kernel.org
- web nvd.nist.gov
- web github.com