High

CVE-2026-98130 — sctp: fix a TOCTOU race in SCTP_CMD_TIMER_START

In the Linux kernel, the following vulnerability has been resolved: sctp: fix a TOCTOU race in SCTP_CMD_TIMER_START The SCTP_CMD_TIMER_START handler checks timer_pending() before calling timer_reduce(). The timer can expire and detach between these operations, causing timer_reduce() to rearm the timer without taking the association reference required for the newly armed timer. The timer callback later unconditionally drops its association reference, which can leave the association reference count unbalanced and result in use-after-free during association teardown. Use the return value of timer_reduce() to determine whether the timer was actually armed. Take the association reference only when timer_reduce() successfully starts a new timer, closing the race between checking the timer state and rearming it. This issue was reported by Nico Yip (@_cyeaa_) working with TrendAI Zero Day Initiative.

Published Sep 25, 2026 · Updated Oct 15, 2026 · Sources: NIST National Vulnerability Database, CVE Program (cve.org) e CISA ADP · CNA: Linux

Low

Who exploits it and how urgent it is

A 0–100 score combining confirmed exploitation, ransomware and APT use, public exploits, EPSS and severity.

No exploitation signal in the sources consulted so far.

How the score was calculated

EPSS 0.6% (30-day exploitation probability)+7
Technical severity (high)+6

The score orders the patch queue; it does not replace your asset context (internet exposure, criticality, compensating controls).

Triage

Is it exploited, how likely is exploitation, what does it touch, and how severe do the sources call it.

Exploitation

Not confirmed

Not in CISA KEV — an absence of record, not proof it is unexploited.

EPSS FIRST

0.58%

ahead of 46% of scored CVEs · Oct 15, 2026

Affects

Linux

CVSS base

8.1

High · 2 source(s)

Remediation

Fixes and mitigations documented by the sources — linked to the original advisory.

No fix documented by the sources we poll. That does not mean none exists: check the vendor advisory.

First 24 hours

Ordered from the record’s own fields — exposure first, because you cannot patch what you have not found. A rule-generated starting point.

Identify exposed assets running the affected vendor/product/version combinations (Linux Linux).
The attack is network-based and needs no privileges: restrict exposure (ACLs, VPN, WAF) until patched.
No fix documented in the sources: reduce exposure and monitor the vendor advisory.
Search available logs for exploit probes, errors and authentication anomalies.

Affected scope

Vendor, product and versions as the sources word them.

Vendor	Product	Versions	Status	Source
Linux	Linux	≥ 20a785aa52c82246055a089e55df9dac47d67da1 and < cbf2df9aac4202f9fb0b361a7fe8c79b29fad92c≥ 20a785aa52c82246055a089e55df9dac47d67da1 and < 3205a20f837f5b1f009427ac3d9f706bf8a6fbec≥ 20a785aa52c82246055a089e55df9dac47d67da1 and < 755d70ca845fd9b87c7b338ae6ae832b08cd0005≥ 20a785aa52c82246055a089e55df9dac47d67da1 and < 09e7f9290d63178f56095d5c18fb9f9470153db5≥ 20a785aa52c82246055a089e55df9dac47d67da1 and < e42ba56281ca3ae2dcb3558bebee9a1c9a4831d9≥ 20a785aa52c82246055a089e55df9dac47d67da1 and < 00b841bac10230c557be6b38efc48508198fe23e≥ 20a785aa52c82246055a089e55df9dac47d67da1 and < 3d698d1e6c8bc41e3e1707777a016f1bdd07842d≥ 20a785aa52c82246055a089e55df9dac47d67da1 and < 2188569e7e1b0bc3f3b557dc97ab7a02befc11c8 and 7 more version 9c0a4652f750afe3b4468cbcd9335b244ce2facdversion 70989e501fbce502198d82da88358ce453575a05version 085bb270b4b1168c93afb37bbafc881207d15443≥ 4.19.126 and < 4.20≥ 5.4.44 and < 5.5≥ 5.6.16 and < 5.7version 5.7	Vulnerable	CVE Program (cve.org) e CISA ADP

Attack characteristics

The CVSS vector, decoded. It describes the attack, not your exposure to it.

Attack vector

Network

Attack complexity

High

Privileges required

None

User interaction

None

Scope

Unchanged

Confidentiality

High

Integrity

High

Availability

High

Every base score collected

Sources score independently and may disagree; each row says who scored it and under which version.

Score	Version	Severity	Expl.	Impact	Scored by
8.1	CVSS 3.1	High	2.2	5.9	416baaa9-dc9f-4396-8d5f-8c081fb06d67 via NIST National Vulnerability Database
8.1	CVSS 3.1	High	—	—	Linux via CVE Program (cve.org) e CISA ADP

CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H (score shown at the top: 416baaa9-dc9f-4396-8d5f-8c081fb06d67)

Detection

Read off the CVSS vector and the weakness class. Starting points, not tested rules.

Prioritize edge telemetry for the network-reachable component (proxy, WAF, IDS/IPS).

web/proxy/WAF logsnetwork IDS/IPS

Timeline

What happened to this CVE, newest first.

2026
Affected products added · linux/linux
Oct 15, 2026 · CVE Program (cve.org) e CISA ADP
Record published
Oct 15, 2026
CVSS changed · 8.1
Oct 15, 2026 · NIST National Vulnerability Database
Source status changed · → Undergoing Analysis
Oct 15, 2026 · NIST National Vulnerability Database
Record created in this database
Oct 15, 2026 · NIST National Vulnerability Database
CVE published
Sep 25, 2026 · Linux

Source activity

Repeated readings are counted rather than listed.

1× Official description updated · Oct 15, 2026 – Oct 15, 2026

References

8 on the record

git.kernel.org/stable/c/755d70ca845fd9b87c7b338ae6ae832b08cd0005
NIST National Vulnerability Database
git.kernel.org/stable/c/09e7f9290d63178f56095d5c18fb9f9470153db5
NIST National Vulnerability Database
git.kernel.org/stable/c/2188569e7e1b0bc3f3b557dc97ab7a02befc11c8
NIST National Vulnerability Database
git.kernel.org/stable/c/3d698d1e6c8bc41e3e1707777a016f1bdd07842d
NIST National Vulnerability Database
git.kernel.org/stable/c/00b841bac10230c557be6b38efc48508198fe23e
NIST National Vulnerability Database
git.kernel.org/stable/c/3205a20f837f5b1f009427ac3d9f706bf8a6fbec
NIST National Vulnerability Database
git.kernel.org/stable/c/cbf2df9aac4202f9fb0b361a7fe8c79b29fad92c
NIST National Vulnerability Database
git.kernel.org/stable/c/e42ba56281ca3ae2dcb3558bebee9a1c9a4831d9
NIST National Vulnerability Database

Elsewhere on this site

Linux
every CVE for this vendor

Related CVEs (same products)

Critical CVE-2026-99999 ipv4: validate checksum_start before completing checksum 16h
Unknown CVE-2026-98432 ipv4: free inet_opt and ireq_opt after an RCU grace period 16h
Unknown CVE-2026-98431 RDMA/uverbs: Fix mmap_lock/disassociation_lock circular dependency 1d
Unknown CVE-2026-98430 RDMA/efa: Keep admin queues alive while IRQ is registered 1d
Unknown CVE-2026-98429 RDMA/efa: Keep EQ resources alive while IRQ is registered 1d
Unknown CVE-2026-98428 ALSA: usb: 6fire: Avoid embedded URBs 1d

Not in any source we poll

Listed rather than left blank: an empty field and an unmeasured one look identical on screen, and only one is a reason to look elsewhere.

No fixed version, patch or mitigation documented.
No CISA SSVC assessment.
No CWE classification.
No confirmed IOCs, IP addresses, domains, file hashes, or malware artifacts supplied.
No organization-specific asset inventory, compensating-control status, or patch deployment evidence supplied.
No exploit packet captures, log samples, or incident case IDs supplied.

Answered from this record

Text assembled only from the fields above — no additional claims.

What should defenders know first?

CVE-2026-98130 is "sctp: fix a TOCTOU race in SCTP_CMD_TIMER_START", rated High. It affects Linux (Linux); versions are in the scope table. It is not in CISA KEV, which does not rule out exploitation. CVSS 8.1 describes technical severity. EPSS 0.58% estimates the probability of exploitation in 30 days; neither replaces your asset context. First verify whether exposed or business-critical assets run the affected versions, apply vendor fixes or mitigations, and preserve logs for review.

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