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TI-2026-38488 Aliases CVE-2026-53402GHSA-jxr7-x2hm-5g42

fbdev: fbcon: fix out-of-bounds read in err_out of fbcon_do_set_font()

Priority LOW 30CWE-125Published · Updated

Key facts

Attack vector
Local
Privileges required
Low
User interaction
None
Attack complexity
Low
Impact type
—
Confidentiality · integrity · availability
High · None · High
Fix status
Partial Red Hat: 2 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: fbdev: fbcon: fix out-of-bounds read in err_out of fbcon_do_set_font() When fbcon_do_set_font() fails (e.g., due to a memory allocation failure inside vc_resize() under heavy memory pressure), it jumps to the `err_out` label to roll back the console state. However, the current rollback logic forgets to restore the `hi_font` state, leading to a severe state machine corruption. Earlier in the function, `set_vc_hi_font()` might be called to change `vc->vc_hi_font_mask` and mutate the screen buffer. If `vc_resize()` subsequently fails, the `err_out` path restores `vc_font.charcount` but entirely skips rolling back the `vc_hi_font_mask` and the screen buffer. This mismatch leaves the terminal in a desynchronized state. Because `vc_hi_font_mask` remains set, the VT subsystem will still accept character indices greater than 255 from userspace and write them to the screen buffer. Subsequent rendering calls (e.g., `fbcon_putcs()`) will then use these inflated indices to access the reverted, 256-character font array, leading to a deterministic out-of-bounds read and potential kernel memory disclosure. Fix this by adding the missing rollback logic for the `hi_font` mask and screen buffer in the error path.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00171 6th percentileScored 2026-11-07
Fix Partial Linux (Linux): 5.10.261, 5.15.212, 5.20 +6Red Hat: 2 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

VendorProductAffected versionsFixed inStatusSource
LinuxLinux5.10.249 to before 5.10.261; 5.15.64 to before 5.15.212; 5.19.6 to before 5.205.10.261, 5.15.212, 5.20Patch availableCNA
LinuxLinux6.0 and later5.10.261, 5.15.212, 6.1.178, 6.6.145, 6.12.96, 6.18.39, 7.1.3, 7.2Patch availableCNA
  • Linux VendorLinux Affected 5.10.249 to before 5.10.261; 5.15.64 to before 5.15.212; 5.19.6 to before 5.20 Fixed in 5.10.261, 5.15.212, 5.20 Patch available CNA
  • Linux VendorLinux Affected 6.0 and later Fixed in 5.10.261, 5.15.212, 6.1.178, 6.6.145, 6.12.96, 6.18.39, 7.1.3, 7.2 Patch available CNA

CPE configurations NVD · 7

CPEVersionsRoleVendor
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*5.10.249 to before 5.10.261; 5.15.64 to before 5.15.212; 5.19.6 to before 6.0; 6.0.1 to before 6.1.178; 6.2 to before 6.6.145; 6.7 to before 6.12.96; 6.13 to before 6.18.39; 6.19 to before 7.1.3VulnerableLinux
cpe:2.3:o:linux:linux_kernel:6.0:-:*:*:*:*:*:*6.0VulnerableLinux
cpe:2.3:o:linux:linux_kernel:6.0:rc3:*:*:*:*:*:*6.0 rc3VulnerableLinux
cpe:2.3:o:linux:linux_kernel:6.0:rc4:*:*:*:*:*:*6.0 rc4VulnerableLinux
cpe:2.3:o:linux:linux_kernel:6.0:rc5:*:*:*:*:*:*6.0 rc5VulnerableLinux
cpe:2.3:o:linux:linux_kernel:6.0:rc6:*:*:*:*:*:*6.0 rc6VulnerableLinux
cpe:2.3:o:linux:linux_kernel:6.0:rc7:*:*:*:*:*:*6.0 rc7VulnerableLinux
  • cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* Versions 5.10.249 to before 5.10.261; 5.15.64 to before 5.15.212; 5.19.6 to before 6.0; 6.0.1 to before 6.1.178; 6.2 to before 6.6.145; 6.7 to before 6.12.96; 6.13 to before 6.18.39; 6.19 to before 7.1.3 Vulnerable ·Linux
  • cpe:2.3:o:linux:linux_kernel:6.0:-:*:*:*:*:*:* Versions 6.0 Vulnerable ·Linux
  • cpe:2.3:o:linux:linux_kernel:6.0:rc3:*:*:*:*:*:* Versions 6.0 rc3 Vulnerable ·Linux
  • cpe:2.3:o:linux:linux_kernel:6.0:rc4:*:*:*:*:*:* Versions 6.0 rc4 Vulnerable ·Linux
  • cpe:2.3:o:linux:linux_kernel:6.0:rc5:*:*:*:*:*:* Versions 6.0 rc5 Vulnerable ·Linux
  • cpe:2.3:o:linux:linux_kernel:6.0:rc6:*:*:*:*:*:* Versions 6.0 rc6 Vulnerable ·Linux
  • cpe:2.3:o:linux:linux_kernel:6.0:rc7:*:*:*:*:*:* Versions 6.0 rc7 Vulnerable ·Linux

Remediation

  • Fix · CNA Linux (Linux) Fixed in 5.10.261, 5.15.212, 5.20
  • Fix · CNA Linux (Linux) Fixed in 5.10.261, 5.15.212, 6.1.178, 6.6.145, 6.12.96, 6.18.39, 7.1.3, 7.2

Vendor assessments

Red Hat

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

ProductStatusPlan or fix
Red Hat Enterprise Linux 10AffectedNo fix yet
Red Hat Enterprise Linux 9AffectedNo fix yet
Not affected: 4 products
  • Red Hat Enterprise Linux 6
  • Red Hat Enterprise Linux 7
  • Red Hat Enterprise Linux 8
  • Red Hat Enterprise Linux 9

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-53402
  2. 2026-10-03 Alias added: GHSA-jxr7-x2hm-5g42
  3. 2026-10-16 CISA SSVC decision points changed
  4. 2026-10-19 Weakness changed · CISA ADP
  5. 2026-10-29 Affected versions changed · Red Hat
  6. 2026-11-03 Affected versions changed · Red Hat
  7. 2026-11-03 CVSS score changed · Red Hat

References

Patch 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-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
  • TI-2021-05514 Heap Out-Of-Bounds Write in Netfilter IP6T_SO_SET_REPLACE KEVCVSS 3.1HIGH 8.3
See all 15278 →

Sources

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