Skip to main content

Linux Kernel CVE-2022-50511

MEDIUM
2025-10-07 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Linux Integer Overflow Denial Of Service Linux Kernel Red Hat Suse
5.5
CVSS 3.1 · NVD
Share

Severity by source

NVD PRIMARY
5.5 MEDIUM
AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
SUSE
MEDIUM
qualitative
Red Hat
4.4 LOW
qualitative

Primary rating from NVD.

CVSS VectorNVD

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Attack Vector
Local
Attack Complexity
Low
Privileges Required
Low
User Interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
None
Availability
High

Lifecycle Timeline

3
Analysis Generated
Mar 17, 2026 - 20:45 vuln.today
Patch released
Mar 17, 2026 - 20:45 nvd
Patch available
CVE Published
Oct 07, 2025 - 16:15 nvd
MEDIUM 5.5

DescriptionCVE.org

In the Linux kernel, the following vulnerability has been resolved:

lib/fonts: fix undefined behavior in bit shift for get_default_font

Shifting signed 32-bit value by 31 bits is undefined, so changing significant bit to unsigned. The UBSAN warning calltrace like below:

UBSAN: shift-out-of-bounds in lib/fonts/fonts.c:139:20 left shift of 1 by 31 places cannot be represented in type 'int' <TASK> dump_stack_lvl+0x7d/0xa5 dump_stack+0x15/0x1b ubsan_epilogue+0xe/0x4e __ubsan_handle_shift_out_of_bounds+0x1e7/0x20c get_default_font+0x1c7/0x1f0 fbcon_startup+0x347/0x3a0 do_take_over_console+0xce/0x270 do_fbcon_takeover+0xa1/0x170 do_fb_registered+0x2a8/0x340 fbcon_fb_registered+0x47/0xe0 register_framebuffer+0x294/0x4a0 __drm_fb_helper_initial_config_and_unlock+0x43c/0x880 [drm_kms_helper] drm_fb_helper_initial_config+0x52/0x80 [drm_kms_helper] drm_fbdev_client_hotplug+0x156/0x1b0 [drm_kms_helper] drm_fbdev_generic_setup+0xfc/0x290 [drm_kms_helper] bochs_pci_probe+0x6ca/0x772 [bochs] local_pci_probe+0x4d/0xb0 pci_device_probe+0x119/0x320 really_probe+0x181/0x550 __driver_probe_device+0xc6/0x220 driver_probe_device+0x32/0x100 __driver_attach+0x195/0x200 bus_for_each_dev+0xbb/0x120 driver_attach+0x27/0x30 bus_add_driver+0x22e/0x2f0 driver_register+0xa9/0x190 __pci_register_driver+0x90/0xa0 bochs_pci_driver_init+0x52/0x1000 [bochs] do_one_initcall+0x76/0x430 do_init_module+0x61/0x28a load_module+0x1f82/0x2e50 __do_sys_finit_module+0xf8/0x190 __x64_sys_finit_module+0x23/0x30 do_syscall_64+0x58/0x80 entry_SYSCALL_64_after_hwframe+0x63/0xcd </TASK>

AnalysisAI

This vulnerability is an undefined behavior issue in the Linux kernel's font handling code where a signed 32-bit left shift by 31 bits violates C language semantics, detected by UBSAN (Undefined Behavior Sanitizer). The vulnerability affects multiple Linux kernel versions starting from 2.6.23 and can be triggered by local users with low privileges during framebuffer console initialization, leading to denial of service through undefined behavior exploitation. While the EPSS score is extremely low at 0.01% (percentile 3%), patches are available from the kernel vendor and the issue has been resolved in stable releases.

Technical ContextAI

The vulnerability exists in lib/fonts/fonts.c in the get_default_font() function, where a signed integer (type 'int') undergoes a left bit shift operation by 31 positions. In C, shifting a signed value such that the result cannot be represented in the type's range constitutes undefined behavior. The affected code path is triggered during framebuffer console startup (fbcon_startup), which executes during display driver registration and initialization. The root cause falls under integer overflow and bit manipulation errors. Per CPE data, all Linux kernel versions are potentially affected, with explicit mention of versions from 2.6.23 through recent releases. The vulnerable code is activated when graphics drivers like DRM (Direct Rendering Manager) and framebuffer helpers initialize, particularly during PCI device probing of graphics hardware such as BOCHS or other display adapters.

RemediationAI

Update the Linux kernel to a patched version incorporating one of the stable fixes referenced at kernel.org (commits 6fe888c4d2fb174408e4540bb2d5602b9f507f90 or later). The primary remediation is a simple code change converting the bit shift operand from 'int' to 'unsigned int' in lib/fonts/fonts.c line 139, which eliminates the undefined behavior. Linux distributions should apply this patch through their standard kernel update mechanisms—users should upgrade via their distribution's package manager (apt, yum, dnf, pacman, etc.) to the latest stable kernel version for their supported branch. No interim workarounds are necessary or available, as the vulnerability only manifests during normal driver initialization; however, disabling framebuffer console drivers (if not required for system operation) could prevent triggering the code path. Verify patched kernel versions via kernel.org stable releases or distribution security advisories.

More in Linux Kernel

View all
CVE-2022-0847 HIGH POC
7.8 Mar 10

Linux kernel contains a flaw known as 'Dirty Pipe' where improper pipe buffer flag initialization allows unprivileged lo
CVE-2015-1328 HIGH POC
7.8 Nov 28

The overlayfs implementation in the linux (aka Linux kernel) package before 3.19.0-21.21 in Ubuntu through 15.04 does no
CVE-2017-7308 HIGH POC
7.8 Mar 29

The packet_set_ring function in net/packet/af_packet.c in the Linux kernel through 4.10.6 does not properly validate cer
CVE-2017-16995 HIGH POC
7.8 Dec 27

The check_alu_op function in kernel/bpf/verifier.c in the Linux kernel through 4.4 allows local users to cause a denial

CVE-2017-1000112 HIGH POC
7.0 Oct 05

Linux kernel: Exploitable memory corruption due to UFO to non-UFO path switch. Rated high severity (CVSS 7.0). Public ex
CVE-2015-8660 MEDIUM POC
6.7 Dec 28

The ovl_setattr function in fs/overlayfs/inode.c in the Linux kernel through 4.3.3 attempts to merge distinct setattr op
CVE-2012-0056 MEDIUM POC
6.9 Jan 27

The mem_write function in the Linux kernel before 3.2.2, when ASLR is disabled, does not properly check permissions when
CVE-2014-0038 MEDIUM POC
6.9 Feb 06

The compat_sys_recvmmsg function in net/compat.c in the Linux kernel before 3.13.2, when CONFIG_X86_X32 is enabled, allo
CVE-2016-8655 HIGH POC
7.8 Dec 08

Race condition in net/packet/af_packet.c in the Linux kernel through 4.8.12 allows local users to gain privileges or cau
CVE-2016-0728 HIGH POC
7.8 Feb 08

The join_session_keyring function in security/keys/process_keys.c in the Linux kernel before 4.4.1 mishandles object ref
CVE-2017-0561 CRITICAL POC
9.8 Apr 07

A remote code execution vulnerability in the Broadcom Wi-Fi firmware could enable a remote attacker to execute arbitrary
CVE-2022-2588 MEDIUM POC
5.3 Jan 08

It was discovered that the cls_route filter implementation in the Linux kernel would not remove an old filter from the h

Same technique Integer Overflow

View all
CVE-2014-0497 CRITICAL POC
9.8
CVE-2013-2729 CRITICAL POC
9.8
CVE-2015-8651 HIGH
8.8
CVE-2012-5054 HIGH POC
8.8
CVE-2014-0569 CRITICAL POC
9.3
CVE-2017-3599 HIGH POC
7.5
CVE-2017-7529 HIGH
7.5
CVE-2016-1010 HIGH
8.8

Vendor StatusVendor

SUSE

Severity: Medium
Product Status
Container suse/sle-micro-rancher/5.3:latest Container suse/sle-micro-rancher/5.4:5.4.4.5.89 Image SLES15-SP4-BYOS Image SLES15-SP4-BYOS-Azure Image SLES15-SP4-BYOS-EC2 Image SLES15-SP4-BYOS-GCE Image SLES15-SP4-HPC-BYOS Image SLES15-SP4-HPC-BYOS-Azure Image SLES15-SP4-HPC-BYOS-EC2 Image SLES15-SP4-HPC-BYOS-GCE Image SLES15-SP4-HPC-EC2 Image SLES15-SP4-HPC-GCE Image SLES15-SP4-Hardened-BYOS Image SLES15-SP4-Hardened-BYOS-Azure Image SLES15-SP4-Hardened-BYOS-EC2 Image SLES15-SP4-Hardened-BYOS-GCE Image SLES15-SP4-Manager-Server-4-3-BYOS Image SLES15-SP4-Manager-Server-4-3-BYOS-Azure Image SLES15-SP4-Manager-Server-4-3-BYOS-EC2 Image SLES15-SP4-Manager-Server-4-3-BYOS-GCE Image SLES15-SP4-Micro-5-3-BYOS Image SLES15-SP4-Micro-5-3-BYOS-Azure Image SLES15-SP4-Micro-5-4-BYOS Image SLES15-SP4-Micro-5-4-BYOS-Azure Image SLES15-SP4-SAP Image SLES15-SP4-SAP-Azure Image SLES15-SP4-SAP-EC2 Image SLES15-SP4-SAP-GCE Image SLES15-SP4-SAPCAL Image SLES15-SP4-SAPCAL-Azure Image SLES15-SP4-SAPCAL-EC2 Image SLES15-SP4-SAPCAL-GCE Affected
Container suse/sle-micro/base-5.5:2.0.4-5.8.224 Image SLES15-SP5-BYOS-Azure Image SLES15-SP5-BYOS-EC2 Image SLES15-SP5-BYOS-GCE Image SLES15-SP5-EC2 Image SLES15-SP5-GCE Image SLES15-SP5-HPC-BYOS-Azure Image SLES15-SP5-HPC-BYOS-EC2 Image SLES15-SP5-HPC-BYOS-GCE Image SLES15-SP5-Hardened-BYOS-Azure Image SLES15-SP5-Hardened-BYOS-EC2 Image SLES15-SP5-Hardened-BYOS-GCE Image SLES15-SP5-Micro-5-5 Image SLES15-SP5-Micro-5-5-Azure Image SLES15-SP5-Micro-5-5-BYOS Image SLES15-SP5-Micro-5-5-BYOS-Azure Image SLES15-SP5-Micro-5-5-EC2 Image SLES15-SP5-SAPCAL-Azure Image SLES15-SP5-SAPCAL-EC2 Image SLES15-SP5-SAPCAL-GCE Affected
Container suse/sle-micro/kvm-5.5:2.0.4-3.5.429 Affected
Container suse/sle-micro/rt-5.5:2.0.4-4.5.535 Affected
Image SLES15-SP4-SAP-Azure-LI-BYOS Image SLES15-SP4-SAP-Azure-LI-BYOS-Production Image SLES15-SP4-SAP-Azure-VLI-BYOS Image SLES15-SP4-SAP-Azure-VLI-BYOS-Production Image SLES15-SP4-SAP-BYOS Image SLES15-SP4-SAP-BYOS-Azure Image SLES15-SP4-SAP-BYOS-EC2 Image SLES15-SP4-SAP-BYOS-GCE Image SLES15-SP4-SAP-Hardened Image SLES15-SP4-SAP-Hardened-Azure Image SLES15-SP4-SAP-Hardened-BYOS Image SLES15-SP4-SAP-Hardened-BYOS-Azure Image SLES15-SP4-SAP-Hardened-BYOS-EC2 Image SLES15-SP4-SAP-Hardened-BYOS-GCE Image SLES15-SP4-SAP-Hardened-GCE Affected

Share

CVE-2022-50511 vulnerability details – vuln.today
Back

This site uses cookies essential for authentication and security. No tracking or analytics cookies are used. Privacy Policy