Critical

CVE-2026-74608 — smb: client: Fix use-after-free in cifs_try_adding_channels()

In the Linux kernel, the following vulnerability has been resolved: smb: client: Fix use-after-free in cifs_try_adding_channels() cifs_try_adding_channels() takes a temporary reference to an interface before dropping iface_lock. If cifs_ses_add_channel() fails, it drops that reference and then increments iface->weight_fulfilled. A concurrent interface list refresh can remove the list reference while channel creation is in progress. In that case, the failure-path kref_put() releases the last reference and frees iface. Updating weight_fulfilled afterward then accesses freed memory. Increment weight_fulfilled before dropping the temporary reference, keeping iface alive for the final access.

Published Aug 22, 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 0.5% (30-day exploitation probability)+6
Technical severity (critical)+10

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

0.48%

ahead of 40% of scored CVEs · Oct 14, 2026

Affects

Linux

CVSS base

9.8

Critical · 3 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	≥ cbc53148cc0946b72d62a3c53870cb22ce4ec284 and < 64d7584e62ac8cdc750455c5fdc6008fc2de4f06≥ cff97d683a083b862a8bb24309e0f4d2d928128a and < c292d4686f717c03e5022fc4ae7c782f39a94915≥ 6aac002bcfd554aff6d3ebb55e1660d078d70ab0 and < 47dfac48bce7198ad4f1a388fc8c9491f878ac3b≥ 6aac002bcfd554aff6d3ebb55e1660d078d70ab0 and < 1ffacbadc14530e55b8d86f7b917524f6a0fb891≥ 6aac002bcfd554aff6d3ebb55e1660d078d70ab0 and < 1305eadc6a7d78a8d0a52eee29ddd2d9e8a27805≥ 6aac002bcfd554aff6d3ebb55e1660d078d70ab0 and < 4986410316b1ae0e63c6ce418e4eb196723626e7version 22a6c5b3425f327e7f4c3606a72277dce82c7d83≥ 6.1.78 and < 6.1.183 and 3 more ≥ 6.6.17 and < 6.6.152≥ 6.7.5 and < 6.8version 6.8	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

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
9.8	CVSS 3.1	Critical	3.9	5.9	416baaa9-dc9f-4396-8d5f-8c081fb06d67 via NIST National Vulnerability Database
9.8	CVSS 3.1	Critical	—	—	GitHub, Inc. via GitHub Security Advisories
9.8	CVSS 3.1	Critical	—	—	Linux via CVE Program (cve.org) e CISA ADP

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

EPSS over time FIRST

Oct 13, 2026 → Oct 14, 2026 · 2 reading(s) · max 0.48%

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 14, 2026 · CVE Program (cve.org) e CISA ADP
Record published
Oct 14, 2026
CVSS changed · 9.8
Oct 14, 2026 · NIST National Vulnerability Database
Source status changed · → Received
Oct 14, 2026 · NIST National Vulnerability Database
Record created in this database
Oct 14, 2026 · NIST National Vulnerability Database
CVE published
Aug 22, 2026 · Linux

Source activity

Repeated readings are counted rather than listed.

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

References

8 on the record

git.kernel.org/stable/c/c292d4686f717c03e5022fc4ae7c782f39a94915
NIST National Vulnerability Database
git.kernel.org/stable/c/1ffacbadc14530e55b8d86f7b917524f6a0fb891
NIST National Vulnerability Database
git.kernel.org/stable/c/4986410316b1ae0e63c6ce418e4eb196723626e7
NIST National Vulnerability Database
git.kernel.org/stable/c/64d7584e62ac8cdc750455c5fdc6008fc2de4f06
NIST National Vulnerability Database
nvd.nist.gov/vuln/detail/CVE-2026-74608
GitHub Security Advisories
git.kernel.org/stable/c/47dfac48bce7198ad4f1a388fc8c9491f878ac3b
NIST National Vulnerability Database
git.kernel.org/stable/c/1305eadc6a7d78a8d0a52eee29ddd2d9e8a27805
NIST National Vulnerability Database
github.com/advisories/GHSA-q727-xf93-53j5
GitHub Security Advisories

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 10h
Unknown CVE-2026-98432 ipv4: free inet_opt and ireq_opt after an RCU grace period 10h
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 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-2026-74608 is "smb: client: Fix use-after-free in cifs_try_adding_channels()", rated Critical. It affects Linux (Linux); versions are in the scope table. It is not in CISA KEV, which does not rule out exploitation. CVSS 9.8 describes technical severity. EPSS 0.48% 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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