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TI-2021-22039 Aliases CVE-2021-47383GHSA-h7hm-j4cr-jwhq

tty: Fix out-of-bound vmalloc access in imageblit

Priority LOW 34CWE-125Published · Updated

Key facts

Attack vector
Local
Privileges required
Low
User interaction
None
Attack complexity
Low
Impact type
—
Confidentiality · integrity · availability
High · High · High
Fix status
Partial Red Hat: 16 fixed, 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: tty: Fix out-of-bound vmalloc access in imageblit This issue happens when a userspace program does an ioctl FBIOPUT_VSCREENINFO passing the fb_var_screeninfo struct containing only the fields xres, yres, and bits_per_pixel with values. If this struct is the same as the previous ioctl, the vc_resize() detects it and doesn't call the resize_screen(), leaving the fb_var_screeninfo incomplete. And this leads to the updatescrollmode() calculates a wrong value to fbcon_display->vrows, which makes the real_y() return a wrong value of y, and that value, eventually, causes the imageblit to access an out-of-bound address value. To solve this issue I made the resize_screen() be called even if the screen does not need any resizing, so it will "fix and fill" the fb_var_screeninfo independently.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00265 18th percentileScored 2026-11-07
Fix Partial Linux (Linux): 4.4.286, 4.9.285, 4.14.249 +5Red Hat: 5 advisoriesRed Hat: 16 fixed, 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
LinuxLinux2.6.12 and later4.4.286, 4.9.285, 4.14.249, 4.19.209, 5.4.151, 5.10.71, 5.14.10, 5.15Patch availableCNA
  • Linux VendorLinux Affected 2.6.12 and later Fixed in 4.4.286, 4.9.285, 4.14.249, 4.19.209, 5.4.151, 5.10.71, 5.14.10, 5.15 Patch available CNA

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*before 4.4.286; 4.5 to before 4.9.285; 4.10 to before 4.14.249; 4.15 to before 4.19.209; 4.20 to before 5.4.151; 5.5 to before 5.10.71; 5.11 to before 5.14.10VulnerableLinux
  • cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* Versions before 4.4.286; 4.5 to before 4.9.285; 4.10 to before 4.14.249; 4.15 to before 4.19.209; 4.20 to before 5.4.151; 5.5 to before 5.10.71; 5.11 to before 5.14.10 Vulnerable ·Linux

Remediation

  • Fix · CNA Linux (Linux) Fixed in 4.4.286, 4.9.285, 4.14.249, 4.19.209, 5.4.151, 5.10.71, 5.14.10, 5.15

Red Hat 5 advisories

  • RHSA-2024:8617 Released 2024-10-30 · Red Hat rating Moderate
    kernel security update
    • Red Hat Enterprise Linux AppStream (v. 9) kernel-64k-debug-devel-5.14.0-427.42.1.el9_4, kernel-64k-debug-devel-matched-5.14.0-427.42.1.el9_4, kernel-64k-devel-5.14.0-427.42.1.el9_4 +11
    • Red Hat Enterprise Linux BaseOS (v. 9) bpftool-7.3.0-427.42.1.el9_4, kernel-5.14.0-427.42.1.el9_4, kernel-64k-5.14.0-427.42.1.el9_4 +29
    • Red Hat Enterprise Linux CRB (v. 9) kernel-tools-libs-devel-5.14.0-427.42.1.el9_4, libperf-5.14.0-427.42.1.el9_4
    • Red Hat Enterprise Linux NFV (v. 9) kernel-rt-5.14.0-427.42.1.el9_4, kernel-rt-core-5.14.0-427.42.1.el9_4, kernel-rt-debug-5.14.0-427.42.1.el9_4 +11
    • Red Hat Enterprise Linux RT (v. 9) kernel-rt-5.14.0-427.42.1.el9_4, kernel-rt-core-5.14.0-427.42.1.el9_4, kernel-rt-debug-5.14.0-427.42.1.el9_4 +9
  • RHSA-2024:7000 Released 2024-09-24 · Red Hat rating Important
    kernel security update
    • Red Hat Enterprise Linux BaseOS (v. 8) bpftool-4.18.0-553.22.1.el8_10, kernel-4.18.0-553.22.1.el8_10, kernel-abi-stablelists-4.18.0-553.22.1.el8_10 +19
    • Red Hat Enterprise Linux CRB (v. 8) kernel-tools-libs-devel-4.18.0-553.22.1.el8_10
  • RHSA-2024:7001 Released 2024-09-24 · Red Hat rating Important
    kernel-rt security update
    • Red Hat Enterprise Linux NFV (v. 8) kernel-rt-4.18.0-553.22.1.rt7.363.el8_10, kernel-rt-core-4.18.0-553.22.1.rt7.363.el8_10, kernel-rt-debug-4.18.0-553.22.1.rt7.363.el8_10 +9
    • Red Hat Enterprise Linux RT (v. 8) kernel-rt-4.18.0-553.22.1.rt7.363.el8_10, kernel-rt-core-4.18.0-553.22.1.rt7.363.el8_10, kernel-rt-debug-4.18.0-553.22.1.rt7.363.el8_10 +7
Show 2 more Red Hat advisories
  • RHSA-2024:5364 Released 2024-08-14 · Red Hat rating Important
    kernel security update
    • Red Hat CodeReady Linux Builder EUS (v.9.2) kernel-tools-libs-devel-5.14.0-284.79.1.el9_2
    • Red Hat Enterprise Linux AppStream EUS (v.9.2) kernel-64k-debug-devel-5.14.0-284.79.1.el9_2, kernel-64k-debug-devel-matched-5.14.0-284.79.1.el9_2, kernel-64k-devel-5.14.0-284.79.1.el9_2 +10
    • Red Hat Enterprise Linux BaseOS EUS (v.9.2) bpftool-7.0.0-284.79.1.el9_2, kernel-5.14.0-284.79.1.el9_2, kernel-64k-5.14.0-284.79.1.el9_2 +29
  • RHSA-2024:5365 Released 2024-08-14 · Red Hat rating Important
    kernel-rt security update
    • Red Hat Enterprise Linux Real Time EUS (v.9.2) kernel-rt-5.14.0-284.79.1.rt14.364.el9_2, kernel-rt-core-5.14.0-284.79.1.rt14.364.el9_2, kernel-rt-debug-5.14.0-284.79.1.rt14.364.el9_2 +9
    • Red Hat Enterprise Linux Real Time for NFV EUS (v.9.2) kernel-rt-5.14.0-284.79.1.rt14.364.el9_2, kernel-rt-core-5.14.0-284.79.1.rt14.364.el9_2, kernel-rt-debug-5.14.0-284.79.1.rt14.364.el9_2 +11

Vendor assessments

Red Hat

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

ProductStatusPlan or fix
Red Hat Enterprise Linux 7AffectedNo fix planned: Out of support scope
Red Hat Enterprise Linux 9AffectedNo fix yet
RHOAI-2.13-RHEL-8Fixed—
RHOAI-2.14-RHEL-8Fixed—
Red Hat CodeReady Linux Builder EUS (v.9.2)Fixed RHSA-2024:5364
Red Hat Enterprise Linux AppStream (v. 9)Fixed RHSA-2024:8617
Red Hat Enterprise Linux AppStream EUS (v.9.2)Fixed RHSA-2024:5364
Red Hat Enterprise Linux BaseOS (v. 8)Fixed RHSA-2024:7000
Red Hat Enterprise Linux BaseOS (v. 9)Fixed RHSA-2024:8617
Red Hat Enterprise Linux BaseOS EUS (v.9.2)Fixed RHSA-2024:5364
Red Hat Enterprise Linux CRB (v. 8)Fixed RHSA-2024:7000
Red Hat Enterprise Linux CRB (v. 9)Fixed RHSA-2024:8617
Red Hat Enterprise Linux NFV (v. 8)Fixed RHSA-2024:7001
Red Hat Enterprise Linux NFV (v. 9)Fixed RHSA-2024:8617
Red Hat Enterprise Linux RT (v. 8)Fixed RHSA-2024:7001
Red Hat Enterprise Linux RT (v. 9)Fixed RHSA-2024:8617
Red Hat Enterprise Linux Real Time EUS (v.9.2)Fixed RHSA-2024:5365
Red Hat Enterprise Linux Real Time for NFV EUS (v.9.2)Fixed RHSA-2024:5365
Not affected: 1 product
  • Red Hat Enterprise Linux 6

Timeline

  1. 2026-10-02 Threatist record created from CVE-2021-47383
  2. 2026-10-03 Alias added: GHSA-h7hm-j4cr-jwhq
  3. 2026-10-30 Fix available: RHOAI-2.13-RHEL-8, RHOAI-2.14-RHEL-8 · 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