High

CVE-2026-74492 — netfilter: ipset: do not update comments from kernel-side hash adds

In the Linux kernel, the following vulnerability has been resolved: netfilter: ipset: do not update comments from kernel-side hash adds mtype_resize() copies comment pointers with memcpy(), not the comment objects themselves. During the window after an entry has been copied but before the table swap and backlog replay, the old table is still published for packet-side updates while the replacement-table entry already holds the same ip_set_comment_rcu pointer. If xt_SET --add-set ... --exist hits that old entry in this window, mtype_add() calls ip_set_init_comment() even though packet-side adds carry no comment payload. That call frees the shared comment through the old entry, so the replacement-table entry now holds a stale pointer. When the queued add is replayed on the new table, mtype_add() calls ip_set_init_comment() again and strlen() dereferences the stale pointer. Fix this in mtype_add() by skipping ip_set_init_comment() when ext->target marks a packet-side add. Userspace adds still update comments, while packet-side adds can no longer free comment storage shared with a resize copy.

Published Aug 15, 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

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

—

No EPSS score.

Affects

Linux

CVSS base

8.4

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).
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	≥ f66ee0410b1c3481ee75e5db9b34547b4d582465 and < 6f13f4d52d06986c18f12e8bffaab944dd27ceab≥ f66ee0410b1c3481ee75e5db9b34547b4d582465 and < f9d6cabff1fca010562dcdb0d22b296bdca3ba5a≥ f66ee0410b1c3481ee75e5db9b34547b4d582465 and < 16bfa7be2d76ca1e0aacfa363482e1bf8ab5042a≥ f66ee0410b1c3481ee75e5db9b34547b4d582465 and < 661ff9c0cfbe07f8eed920dde9f7781491738207≥ f66ee0410b1c3481ee75e5db9b34547b4d582465 and < c710e9bf38e4e71a8db85d26a0f70c0674664207≥ f66ee0410b1c3481ee75e5db9b34547b4d582465 and < 4ae701848e4ba9e9713375fb7d82218cbd309da2≥ f66ee0410b1c3481ee75e5db9b34547b4d582465 and < 77dbb248a5cc7a5270cd37bbb0b635bf059a872a≥ f66ee0410b1c3481ee75e5db9b34547b4d582465 and < f30415929be8aeb002d557c8d3f7ab2d2188003a and 5 more version 5dd9488ae41070b69d2f4acb580f77db5705f9caversion a469bab3386aebff33c59506f3a95e35b91118fd≥ 5.4.24 and < 5.5≥ 5.5.8 and < 5.6version 5.6	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

Local

Attack complexity

Low

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
8.4	CVSS 3.1	High	2.5	5.9	416baaa9-dc9f-4396-8d5f-8c081fb06d67 via NIST National Vulnerability Database
8.4	CVSS 3.1	High	—	—	Linux via CVE Program (cve.org) e CISA ADP

CVSS:3.1/AV:L/AC:L/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.

Local/physical vector: focus on endpoint telemetry (EDR) from affected hosts.

endpoint telemetry (EDR)

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 · 8.4
Oct 15, 2026 · NIST National Vulnerability Database
Source status changed · → Received
Oct 15, 2026 · NIST National Vulnerability Database
Record created in this database
Oct 15, 2026 · NIST National Vulnerability Database
CVE published
Aug 15, 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/c710e9bf38e4e71a8db85d26a0f70c0674664207
NIST National Vulnerability Database
git.kernel.org/stable/c/77dbb248a5cc7a5270cd37bbb0b635bf059a872a
NIST National Vulnerability Database
git.kernel.org/stable/c/f9d6cabff1fca010562dcdb0d22b296bdca3ba5a
NIST National Vulnerability Database
git.kernel.org/stable/c/6f13f4d52d06986c18f12e8bffaab944dd27ceab
NIST National Vulnerability Database
git.kernel.org/stable/c/661ff9c0cfbe07f8eed920dde9f7781491738207
NIST National Vulnerability Database
git.kernel.org/stable/c/f30415929be8aeb002d557c8d3f7ab2d2188003a
NIST National Vulnerability Database
git.kernel.org/stable/c/16bfa7be2d76ca1e0aacfa363482e1bf8ab5042a
NIST National Vulnerability Database
git.kernel.org/stable/c/4ae701848e4ba9e9713375fb7d82218cbd309da2
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 14h
Unknown CVE-2026-98432 ipv4: free inet_opt and ireq_opt after an RCU grace period 14h
Unknown CVE-2026-98424 wifi: cfg80211: undo netns switch if renaming the wiphy fails 1d
Unknown CVE-2026-98425 wifi: mac80211: don't warn when an IBSS has no channel to scan 1d
Unknown CVE-2026-98426 wifi: mwifiex: fix IRQ leak using wrong index in MSI-X error path 1d
Unknown CVE-2026-98427 net/sched: codel: bound the dropping loop per dequeue call 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 FIRST EPSS score.
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-2026-74492 is "netfilter: ipset: do not update comments from kernel-side hash adds", 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 8.4 describes technical severity. 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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