TI-2026-50589 Aliases CVE-2026-72310 GHSA-h4wv-r484-2rg5

smb: client: fix overflow in passthrough ioctl bounds check

LOW 36Published 2026-08-15 · Updated 2026-10-16

Key facts

Attack vector: Network
Privileges required: Low
User interaction: None
Attack complexity: Low
Impact type: —
Confidentiality · integrity · availability: High · None · High
Fix status: Partial Red Hat: 3 without a fix

Attack profile from CVSS 3.1 · CNA. Fix status from CNA and Red Hat.

Summary

In the Linux kernel, the following vulnerability has been resolved: smb: client: fix overflow in passthrough ioctl bounds check smb2_ioctl_query_info() validates the PASSTHRU_FSCTL response payload before copying it to userspace. The payload offset and length both come from 32-bit fields. The bounds check currently adds OutputOffset and qi.input_buffer_length directly, so the addition can wrap in 32-bit arithmetic before the result is compared against the response buffer length. A malicious server can use a large OutputOffset and a small OutputCount to make the wrapped sum pass the bounds check. The later copy_to_user() then reads from io_rsp + OutputOffset, outside the response buffer. Use size_add() for the offset plus length check so overflow is treated as out of bounds.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV

EPSS 0.00643 51st percentileScored 2026-11-07

Fix Partial Linux (Linux): 5.5, 5.10.261, 5.15.212 +6Red Hat: 3 without a fix

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation: None
Automatable: No
Technical impact: Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

Vendor	Product	Affected versions	Fixed in	Status	Source
Linux	Linux	5.4.69 to before 5.5	5.5	Patch available	CNA
Linux	Linux	5.5 and later	5.10.261, 5.15.212, 6.1.178, 6.6.145, 6.12.97, 6.18.40, 7.1.5, 7.2	Patch available	CNA

Linux VendorLinux Affected 5.4.69 to before 5.5 Fixed in 5.5 Patch available CNA
Linux VendorLinux Affected 5.5 and later Fixed in 5.10.261, 5.15.212, 6.1.178, 6.6.145, 6.12.97, 6.18.40, 7.1.5, 7.2 Patch available CNA

CPE names Threatist (inferred) · 1

Inferred from how NVD named this product before; not given by a source.

CPE	Versions	Role	Vendor
cpe:2.3:o:linux:linux_kernel::::::::	—	—	Linux

cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* Versions — — ·Linux

Remediation

Fix · CNA Linux (Linux) Fixed in 5.5
Fix · CNA Linux (Linux) Fixed in 5.10.261, 5.15.212, 6.1.178, 6.6.145, 6.12.97, 6.18.40, 7.1.5, 7.2

Vendor assessments

Red Hat

Red Hat rating: Moderate. Red Hat's page for this CVE →

Product	Status	Plan or fix
Red Hat Enterprise Linux 10	Affected	No fix yet: Fix deferred
Red Hat Enterprise Linux 8	Affected	No fix yet
Red Hat Enterprise Linux 9	Affected	No fix yet

Not affected: 2 products

Red Hat Enterprise Linux 6
Red Hat Enterprise Linux 7

Timeline

2026-10-02 Threatist record created from CVE-2026-72310
2026-10-03 Alias added: GHSA-h4wv-r484-2rg5
2026-10-16 CISA SSVC decision points changed
2026-10-21 EPSS moved to the 50th–90th percentile
2026-11-06 Affected versions changed · Red Hat
2026-11-06 CVSS score changed · Red Hat

References

Other 8

TI-2025-26358 tls: fix handling of zero-length records on the rx_list KEVCVSS 3.1CRITICAL 9.8
TI-2026-38352 netfilter: bridge: make ebt_snat ARP rewrite writable KEVCVSS 3.1HIGH 8.8
TI-2021-02452 Incorrect authorization in Ubuntu linux kernel KEVCVSS 3.1HIGH 8.8
TI-2013-05264 The (1) get_user and (2) put_user API functions in the Linux kernel before 3.5.5 on the… KEVCVSS 3.1HIGH 8.8
TI-2022-00125 Integer overflow in kernel KEVCVSS 3.1HIGH 8.4
TI-2013-01864 The perf_swevent_init function in kernel/events/core.c in the Linux kernel before 3.8.9… KEVCVSS 3.1HIGH 8.4

See all 21741 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences