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TI-2026-62805 Aliases CVE-2026-93186GHSA-4xf9-vh86-48mc

cxl/mbox: Clamp mailbox output allocation to the payload size

Priority LOW 22Published · Updated

Key facts

Attack vector
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Privileges required
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User interaction
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Attack complexity
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Impact type
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Confidentiality · integrity · availability
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Fix status
Partial Red Hat: 4 without a fix

No CVSS vector from any source. Fix status from CNA and Red Hat.

Summary

In the Linux kernel, the following vulnerability has been resolved: cxl/mbox: Clamp mailbox output allocation to the payload size CXL_MEM_SEND_COMMAND bounds the user's in.size to the mailbox payload size but leaves out.size unbounded, then cxl_mbox_cmd_ctor() calls kvzalloc(out.size). A large out.size drives a huge allocation, above INT_MAX it WARNs and taints, and with panic_on_warn=1 it panics. The transport __cxl_pci_mbox_send_cmd() already clamps the response copy to min(out.size, payload_size, device len), so the output buffer is never written beyond payload_size. Clamp the allocation to payload_size too, matching the RAW path.

Why it matters now

EPSS 0.00199 9th percentileScored 2026-11-07
Fix Partial Linux (Linux): 6.1.191, 6.6.160, 6.12.110 +3Red Hat: 4 without a fix

SSVC decision points

Not available: CISA has not published SSVC decision points for this record.

Affected products

VendorProductAffected versionsFixed inStatusSource
LinuxLinux5.12 and later6.1.191, 6.6.160, 6.12.110, 6.18.52, 7.2.6, 7.3Patch availableCNA
  • Linux VendorLinux Affected 5.12 and later Fixed in 6.1.191, 6.6.160, 6.12.110, 6.18.52, 7.2.6, 7.3 Patch available CNA

CPE names Threatist (inferred) · 1

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

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

Remediation

  • Fix · CNA Linux (Linux) Fixed in 6.1.191, 6.6.160, 6.12.110, 6.18.52, 7.2.6, 7.3

Vendor assessments

Red Hat

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

ProductStatusPlan or fix
Red Hat Enterprise Linux 10AffectedNo fix yet: Fix deferred
Red Hat Enterprise Linux 9AffectedNo fix yet: Fix deferred
Red Hat OpenShift Container Platform 4AffectedNo fix yet: Fix deferred
Red Hat OpenShift Container Platform 5AffectedNo fix yet: Fix deferred
Not affected: 4 products
  • Red Hat Enterprise Linux 6
  • Red Hat Enterprise Linux 7
  • Red Hat Enterprise Linux 8
  • Red Hat OpenShift Container Platform 4

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-93186
  2. 2026-10-03 Alias added: GHSA-4xf9-vh86-48mc
  3. 2026-10-15 Affected versions changed · Red Hat
  4. 2026-10-15 CVSS score added · Red Hat
  5. 2026-10-19 Fix available: Linux/[email protected] · CNA
  6. 2026-10-21 Fix available: Linux/[email protected], Linux/Linux@d2d40574b9b272ade32d0d77b140d990e7547f5f · CNA
  7. 2026-10-21 1 new reference · CNA
  8. 2026-10-30 Fix available: Linux/Linux@123f6d154253939ce38f0ec0b6d1ba67f870e01f, Linux/[email protected] · CNA
  9. 2026-10-30 1 new reference · CNA
  10. 2026-11-07 Affected versions changed · Red Hat

References

Other 6

  • 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