High Memory corruption

CVE-2026-23351 — netfilter: nft_set_pipapo: split gc into unlink and reclaim phase

In the Linux kernel, the following vulnerability has been resolved: netfilter: nft_set_pipapo: split gc into unlink and reclaim phase Yiming Qian reports Use-after-free in the pipapo set type: Under a large number of expired elements, commit-time GC can run for a very long time in a non-preemptible context, triggering soft lockup warnings and RCU stall reports (local denial of service). We must split GC in an unlink and a reclaim phase. We cannot queue elements for freeing until pointers have been swapped. Expired elements are still exposed to both the packet path and userspace dumpers via the live copy of the data structure. call_rcu() does not protect us: dump operations or element lookups starting after call_rcu has fired can still observe the free'd element, unless the commit phase has made enough progress to swap the clone and live pointers before any new reader has picked up the old version. This a similar approach as done recently for the rbtree backend in commit 35f83a75529a ("netfilter: nft_set_rbtree: don't gc elements on insert").

Published Mar 25, 2026 · Updated Oct 14, 2026 · Sources: NIST National Vulnerability Database, CVE Program (cve.org) e CISA ADP, GitHub Security Advisories · 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 0.1% (30-day exploitation probability)+0
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

0.13%

ahead of 2% of scored CVEs · Oct 14, 2026

Affects

Linux

Linux and 1 more

CVSS base

7.8

High · 3 source(s)

Remediation

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

Documented patch — git.kernel.org (NIST National Vulnerability Database)
Documented patch — git.kernel.org (NIST National Vulnerability Database)
Documented patch — git.kernel.org (NIST National Vulnerability Database)
Documented patch — git.kernel.org (NIST National Vulnerability Database)
Documented patch — git.kernel.org (NIST National Vulnerability Database)
Documented patch — git.kernel.org (NIST National Vulnerability Database)
Documented patch — git.kernel.org (NIST National Vulnerability Database)
Documented patch — git.kernel.org (NIST National Vulnerability Database)

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, Linux Linux Kernel).
Apply the fixed version or the patch documented under Remediation.
Search available logs for exploit probes matching the vulnerability class (memory corruption), errors and authentication anomalies.

Affected scope

Vendor, product and versions as the sources word them.

Vendor	Product	Versions	Status	Source
Linux	Linux	version 5.6≥ 3c4287f62044a90e73a561aa05fc46e62da173da and < 9df95785d3d8302f7c066050117b04cd3c2048c2≥ 3c4287f62044a90e73a561aa05fc46e62da173da and < aff13667708dfa0dce136b8efd81baa9fa6ef261≥ 3c4287f62044a90e73a561aa05fc46e62da173da and < 500a50a301ce962b019ab95053ac70264fec2c21≥ 3c4287f62044a90e73a561aa05fc46e62da173da and < c12d570d71920903a1a0468b7d13b085203d0c93≥ 3c4287f62044a90e73a561aa05fc46e62da173da and < 7864c667aed01a58b87ca518a631322cd0ac34c0≥ 3c4287f62044a90e73a561aa05fc46e62da173da and < 16f3595c0441d87dfa005c47d8f95be213afaa9e≥ 3c4287f62044a90e73a561aa05fc46e62da173da and < c0f1f85097ac2b6e7d750fe4d05807985cd3fd3a and 1 more ≥ 3c4287f62044a90e73a561aa05fc46e62da173da and < 65ca51b9fb85477ab92a04295aed34b38f7c062e	Vulnerable	CVE Program (cve.org) e CISA ADP
Linux	Linux Kernel	version 7.0-rc5version 7.0-rc7version 7.0-rc6≥ 5.6.1 and < 5.10.253version 7.0-rc4version 7.0-rc3version 7.0-rc2version 7.0-rc1 and 7 more version 5.6≥ 6.19 and < 6.19.7≥ 6.13 and < 6.18.17≥ 6.7 and < 6.12.77≥ 6.2 and < 6.6.130≥ 5.16 and < 6.1.167≥ 5.11 and < 5.15.203	Vulnerable	NIST National Vulnerability Database

Attack characteristics

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

Attack vector

Local

Attack complexity

Low

Privileges required

Low

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
7.8	CVSS 3.1	High	1.8	5.9	416baaa9-dc9f-4396-8d5f-8c081fb06d67 via NIST National Vulnerability Database
7.8	CVSS 3.1	High	—	—	GitHub, Inc. via GitHub Security Advisories
7.8	CVSS 3.1	High	—	—	Linux via CVE Program (cve.org) e CISA ADP

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

Weakness MITRE

Weakness class according to MITRE’s CWE catalog.

CWE-416 · Use After Free

Other CVEs with this weakness →

EPSS over time FIRST

Oct 13, 2026 → Oct 14, 2026 · 2 reading(s) · max 0.13%

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.
Correlate service crashes/restarts with inbound traffic; repeated crashes may indicate attempts.

endpoint telemetry (EDR)crash dumps

Timeline

What happened to this CVE, newest first.

2026
Affected products added · linux/linux
Oct 13, 2026 · CVE Program (cve.org) e CISA ADP
Record published
Oct 13, 2026
Fix documented
Oct 13, 2026 · NIST National Vulnerability Database
CVSS changed · 7.8
Oct 13, 2026 · NIST National Vulnerability Database
Source status changed · → Modified
Oct 13, 2026 · NIST National Vulnerability Database
Record created in this database
Oct 13, 2026 · NIST National Vulnerability Database
CVE published
Mar 25, 2026 · Linux

Source activity

Repeated readings are counted rather than listed.

2× References added · Oct 14, 2026 – Oct 14, 2026
1× Official description updated · Oct 13, 2026 – Oct 13, 2026

References

14 on the record

git.kernel.org/stable/c/c0f1f85097ac2b6e7d750fe4d05807985cd3fd3a
Patch, NIST National Vulnerability Database
git.kernel.org/stable/c/7864c667aed01a58b87ca518a631322cd0ac34c0
Patch, NIST National Vulnerability Database
git.kernel.org/stable/c/65ca51b9fb85477ab92a04295aed34b38f7c062e
Patch, NIST National Vulnerability Database
git.kernel.org/stable/c/c12d570d71920903a1a0468b7d13b085203d0c93
Patch, NIST National Vulnerability Database
git.kernel.org/stable/c/500a50a301ce962b019ab95053ac70264fec2c21
Patch, NIST National Vulnerability Database
git.kernel.org/stable/c/16f3595c0441d87dfa005c47d8f95be213afaa9e
Patch, NIST National Vulnerability Database
git.kernel.org/stable/c/aff13667708dfa0dce136b8efd81baa9fa6ef261
Patch, NIST National Vulnerability Database
git.kernel.org/stable/c/9df95785d3d8302f7c066050117b04cd3c2048c2
Patch, NIST National Vulnerability Database
cert-portal.siemens.com/productcert/html/ssa-082556.html
NIST National Vulnerability Database
nvd.nist.gov/vuln/detail/CVE-2026-23351
GitHub Security Advisories
github.com/advisories/GHSA-42q3-4jmh-pwqx
GitHub Security Advisories
cert-portal.siemens.com/productcert/html/ssa-457936.html
NIST National Vulnerability Database
cert-portal.siemens.com/productcert/html/ssa-019113.html
NIST National Vulnerability Database
cert-portal.siemens.com/productcert/html/ssa-784472.html
NIST National Vulnerability Database

Elsewhere on this site

Linux
every CVE for this vendor

Memory corruption
same class

CWE-416
other pages naming this weakness

Related CVEs (same products)

Critical CVE-2026-99999 ipv4: validate checksum_start before completing checksum 12h
Unknown CVE-2026-98432 ipv4: free inet_opt and ireq_opt after an RCU grace period 12h
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 CISA SSVC assessment.
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-2026-23351 is "netfilter: nft_set_pipapo: split gc into unlink and reclaim phase", 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 7.8 describes technical severity. EPSS 0.13% 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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