Linux Kernel up to 5.15.103/6.1.20/6.2.7 rdtgroup_mkdir privilege escalation

Summaryinfo

A vulnerability marked as critical has been reported in Linux Kernel up to 5.15.103/6.1.20/6.2.7. Affected by this issue is the function rdtgroup_mkdir. This manipulation causes an unknown weakness. The identification of this vulnerability is CVE-2023-53169. There is no exploit available. It is suggested to upgrade the affected component.

Detailsinfo

A vulnerability classified as critical was found in Linux Kernel up to 5.15.103/6.1.20/6.2.7. The impact remains unknown. The summary by CVE is:

In the Linux kernel, the following vulnerability has been resolved: x86/resctrl: Clear staged_config[] before and after it is used As a temporary storage, staged_config[] in rdt_domain should be cleared before and after it is used. The stale value in staged_config[] could cause an MSR access error. Here is a reproducer on a system with 16 usable CLOSIDs for a 15-way L3 Cache (MBA should be disabled if the number of CLOSIDs for MB is less than 16.) : mount -t resctrl resctrl -o cdp /sys/fs/resctrl mkdir /sys/fs/resctrl/p{1..7} umount /sys/fs/resctrl/ mount -t resctrl resctrl /sys/fs/resctrl mkdir /sys/fs/resctrl/p{1..8} An error occurs when creating resource group named p8: unchecked MSR access error: WRMSR to 0xca0 (tried to write 0x00000000000007ff) at rIP: 0xffffffff82249142 (cat_wrmsr+0x32/0x60) Call Trace: <IRQ> __flush_smp_call_function_queue+0x11d/0x170 __sysvec_call_function+0x24/0xd0 sysvec_call_function+0x89/0xc0 </IRQ> <TASK> asm_sysvec_call_function+0x16/0x20 When creating a new resource control group, hardware will be configured by the following process: rdtgroup_mkdir() rdtgroup_mkdir_ctrl_mon() rdtgroup_init_alloc() resctrl_arch_update_domains() resctrl_arch_update_domains() iterates and updates all resctrl_conf_type whose have_new_ctrl is true. Since staged_config[] holds the same values as when CDP was enabled, it will continue to update the CDP_CODE and CDP_DATA configurations. When group p8 is created, get_config_index() called in resctrl_arch_update_domains() will return 16 and 17 as the CLOSIDs for CDP_CODE and CDP_DATA, which will be translated to an invalid register - 0xca0 in this scenario. Fix it by clearing staged_config[] before and after it is used. [reinette: re-order commit tags]

The advisory is shared at git.kernel.org. This vulnerability is known as CVE-2023-53169 since 09/15/2025. The exploitation appears to be difficult. Technical details are known, but no exploit is available. The price for an exploit might be around USD $0-$5k at the moment (estimation calculated on 01/10/2026).

Upgrading to version 5.15.104, 6.1.21 or 6.2.8 eliminates this vulnerability. Applying the patch 86db319d25db70cf4af4557e05f6fa6f39c70003/3fc5941ecc31a495b6b84b465f36155009db99b5/8ecc60ef9318f0d533b866fa421858cc185bccfc/0424a7dfe9129b93f29b277511a60e87f052ac6b is able to eliminate this problem. The bugfix is ready for download at git.kernel.org. The best possible mitigation is suggested to be upgrading to the latest version.

The vulnerability is also documented in the vulnerability database at CERT Bund (WID-SEC-2025-2053). Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Affected

• Debian Linux
• Amazon Linux 2
• Red Hat Enterprise Linux
• Ubuntu Linux
• SUSE Linux
• Oracle Linux
• IBM QRadar SIEM
• SUSE openSUSE
• Open Source Linux Kernel
• RESF Rocky Linux
• Dell Secure Connect Gateway
• F5 F5OS

Productinfo

Type

• Operating System

Vendor

• Linux

Name

• Kernel

Version

• 5.15.103
• 6.1.0
• 6.1.1
• 6.1.2
• 6.1.3
• 6.1.4
• 6.1.5
• 6.1.6
• 6.1.7
• 6.1.8
• 6.1.9
• 6.1.10
• 6.1.11
• 6.1.12
• 6.1.13
• 6.1.14
• 6.1.15
• 6.1.16
• 6.1.17
• 6.1.18
• 6.1.19
• 6.1.20
• 6.2.0
• 6.2.1
• 6.2.2
• 6.2.3
• 6.2.4
• 6.2.5
• 6.2.6
• 6.2.7

License

• open-source

Website

• Vendor: https://www.kernel.org/

CPE 2.3info

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CPE 2.2info

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Exploitinginfo

Threat Intelligenceinfo

Countermeasuresinfo

Timelineinfo

Sourcesinfo

Entryinfo

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

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