Read the docs
TI-2026-79640 Aliases CVE-2026-98883GHSA-g9xp-whrx-5gjh

Linux kernel 8250 serial driver warns on unrecognized UPIO_AU type

Priority LOW 22Published · Updated

Key facts

Attack vector
—
Privileges required
—
User interaction
—
Attack complexity
—
Impact type
—
Confidentiality · integrity · availability
—
Fix status
Fixed

No CVSS vector from any source. Fix status from CNA.

Summary

The Linux kernel from 6.13 has a flaw in its 8250 serial port driver, which does not recognize the UPIO_AU port type. On MIPS Alchemy systems, probing the driver logs an unsupported UART type warning. The fix treats UPIO_AU as already configured by the platform setup code.

Written with Claude Haiku 5.5 from the sources below · 2026-11-06

Description from the CNA

In the Linux kernel, the following vulnerability has been resolved: serial: 8250_port: recognize UPIO_AU My MIPS Alchemy systems generate the following warning during probe of the 8250 driver: WARNING: drivers/tty/serial/8250/8250_port.c:462 at set_io_from_upio+0xfc/0x124, CPU#0: swapper/0/1 Unsupported UART type 4 [...] [<80521d40>] set_io_from_upio+0xfc/0x124 [<80521dfc>] serial8250_set_defaults+0x94/0xe0 [<80520fb4>] serial8250_register_8250_port+0x288/0x51c [<805214ec>] serial8250_probe+0x160/0x1e8 [<8053b5f0>] platform_probe+0x64/0x90 The least invasive fix is to recognize UPIO_AU (type 4) in set_io_from_upio() and do nothing, since all parameters have already been set up in 8250_rt288x.c::au_platform_setup(). Run-tested on Alchemy Au1300 platform.

Why it matters now

EPSS 0.00161 5th percentileScored 2026-11-07
Fix Fixed Linux (Linux): 6.18.53, 7.2

SSVC decision points

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

Affected products

VendorProductAffected versionsFixed inStatusSource
LinuxLinux6.13 and later6.18.53, 7.2Patch availableCNA
  • Linux VendorLinux Affected 6.13 and later Fixed in 6.18.53, 7.2 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

Fixed versions are Linux kernel 6.18.53 and 7.2.

Written with Claude Haiku 5.5 from the sources below · 2026-11-06

  • Fix · CNA Linux (Linux) Fixed in 6.18.53, 7.2

Vendor assessments

Red Hat

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

Not affected: 6 products
  • Red Hat Enterprise Linux 10
  • Red Hat Enterprise Linux 6
  • Red Hat Enterprise Linux 7
  • Red Hat Enterprise Linux 8
  • Red Hat Enterprise Linux 9
  • Red Hat OpenShift Container Platform 4

Timeline

  1. 2026-10-23 Threatist record created from CVE-2026-98883
  2. 2026-10-23 Alias added: GHSA-g9xp-whrx-5gjh
  3. 2026-10-26 Fix available: Linux/Linux@0 · CNA
  4. 2026-10-26 Affected versions changed · Red Hat
  5. 2026-10-26 CVSS score added · Red Hat

References

  • 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 21727 →

Sources