MediumCVE-2023-52570

Linux Kernel: NULL Pointer Dereference (CVE-2023-52570)

Published 02.03.2024Sources: BSI, EUVD, CVE.org

What is affected, what to do

Update Linux Kernel to version 6.1.56, Linux Kernel to version 6.5.6, Linux Kernel to version 6.6.

Affected: Linux Kernel lt 6.1..6.1.56
Linux Kernel lt 6.2..6.5.6
Fixed in: Linux Kernel 6.1.56
Linux Kernel 6.5.6
Linux Kernel 6.6

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Metrics

5.5

XIEM Effective CVSS

Highest available CVSS rating from NVD and vendor data.

Source: NVD, CVSS v3

5.5

CVSS v3

Severity Medium on the scale from 0 to 10.

Source: BSI, EUVD, CVE.org

0.2 %

EPSS score

Low — model estimates < 1% exploitation likelihood.

Source: FIRST EPSS, percentile 12.9

Show all metrics

Severity: Medium
Priority (0–325) The priority score is a consolidated metric that condenses several individual signals into a single, action-guiding ranking: technical severity (CVSS), exploitation likelihood (EPSS), known-exploited status (KEV) and the context of the affected asset. The aim is to answer the only truly important question in vulnerability management: what first? Read in glossary: 33.33 Methodology
Exploit maturity An exploit is code or a technique that specifically uses a concrete vulnerability to force unintended behaviour — such as executing code or escalating privileges. It is the tool that turns a theoretical flaw into a practical attack. Read in glossary: no public PoC known
XIEM Effective CVSS XIEM® is the tiered managed-security operating model from NEOSEC and a registered trademark of NEOSEC GmbH. It extends classic SIEM — the central collection, normalisation and correlation of security-relevant events — with endpoint forensics, network visibility and deception technology, and consolidates them into three building tiers: Sentry, Orchestrate and Command. Read in glossary: 5.5 Methodology
CVSS v3 CVSS is the globally established, open standard for assessing the technical severity of a vulnerability on a scale from 0 to 10. It describes how easily a flaw can be exploited and what damage it can cause — but not how likely its actual exploitation is. CVSS and the complementary EPSS deliberately answer different questions. Read in glossary: 5.5
EPSS score The EPSS score is the absolute model output for an individual vulnerability: the estimated probability of real-world exploitation within the next 30 days, expressed as a value between 0 and 1 (i.e. 0 % to 100 %). A score of 0.42 means „the model estimates a 42 % chance of real-world exploitation within 30 days“. Read in glossary: 0.2 %; Low — model estimates < 1% exploitation likelihood.
EPSS percentile The EPSS percentile is the relative position of a vulnerability within all EPSS-scored CVEs, expressed as a value between 0 and 1. A percentile of 0.90 means „this CVE has a higher EPSS score than 90 % of all other scored CVEs“. Unlike the EPSS score, it is not a probability — but a positioning within a ranking. Read in glossary: 12.9; Elevated — this CVE ranks above at least 10% of all CVEs scored today.
KEV status The KEV catalogue is a list maintained by the US authority CISA of vulnerabilities for which active exploitation in the wild has been confirmed. It answers not the question „how severe?“ but „is it already being attacked?“ — thereby sharply prioritising patching. Read in glossary: —
Published: 02.03.2024
CISA assessment (SSVC): Exploitation: none known · not automatable · Technical impact: partial; Source: CISA Vulnrichment, as of 4 March 2024

Detection rules

No NEOSEC detection rule is available for this vulnerability yet.

Classification under NIS2 and CRA

Rule-based classification from exploitation status and severity. It does not replace a case-by-case assessment.

NIS2 NIS2 is EU Directive (EU) 2022/2555 to raise the level of cybersecurity across the Union. It substantially broadens obligations compared with the first NIS directive: more sectors, mandatory risk management, staged reporting duties and personal accountability of senior management. Read in glossary: Handle the vulnerability in regular vulnerability handling under Art. 21(2)(e) NIS2.
CRA The CRA is EU Regulation (EU) 2024/2847 setting horizontal cybersecurity requirements for „products with digital elements“ — from industrial controllers and software to connected consumer devices. For the first time manufacturers must ensure security across the entire product lifecycle, handle vulnerabilities and provide security updates. Read in glossary: From 11.12.2027, Annex I Part II CRA requires manufacturers of affected products with digital elements to handle vulnerabilities without delay and provide security updates.
ISO/IEC 27001 ISO/IEC 27001 is the internationally leading standard for an information security management system (ISMS). It describes a risk-based, process-oriented framework to systematically plan, implement, review and improve information security. Read in glossary: Control A.8.8, management of technical vulnerabilities: assess relevance to your systems, plan remediation and keep evidence.

Description

In the Linux kernel, the following vulnerability has been resolved: vfio/mdev: Fix a null-ptr-deref bug for mdev_unregister_parent() Inject fault while probing mdpy.ko, if kstrdup() of create_dir() fails in kobject_add_internal() in kobject_init_and_add() in mdev_type_add() in parent_create_sysfs_files(), it will return 0 and probe successfully. And when rmmod mdpy.ko, the mdpy_dev_exit() will call mdev_unregister_parent(), the mdev_type_remove() may traverse uninitialized parent->types[i] in parent_remove_sysfs_files(), and it will cause below null-ptr-deref. If mdev_type_add() fails, return the error code and kset_unregister() to fix the issue. general protection fault, probably for non-canonical address 0xdffffc0000000002: 0000 [#1] PREEMPT SMP KASAN KASAN: null-ptr-deref in range [0x0000000000000010-0x0000000000000017] CPU: 2 PID: 10215 Comm: rmmod Tainted: G W N 6.6.0-rc2+ #20 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.15.0-1 04/01/2014 RIP: 0010:__kobject_del+0x62/0x1c0 Code: 48 89 fa 48 c1 ea 03 80 3c 02 00 0f 85 51 01 00 00 48 b8 00 00 00 00 00 fc ff df 48 8b 6b 28 48 8d 7d 10 48 89 fa 48 c1 ea 03 <80> 3c 02 00 0f 85 24 01 00 00 48 8b 75 10 48 89 df 48 8d 6b 3c e8 RSP: 0018:ffff88810695fd30 EFLAGS: 00010202 RAX: dffffc0000000000 RBX: ffffffffa0270268 RCX: 0000000000000000 RDX: 0000000000000002 RSI: 0000000000000004 RDI: 0000000000000010 RBP: 0000000000000000 R08: 0000000000000001 R09: ffffed10233a4ef1 R10: ffff888119d2778b R11: 0000000063666572 R12: 0000000000000000 R13: fffffbfff404e2d4 R14: dffffc0000000000 R15: ffffffffa0271660 FS: 00007fbc81981540(0000) GS:ffff888119d00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fc14a142dc0 CR3: 0000000110a62003 CR4: 0000000000770ee0 DR0: ffffffff8fb0bce8 DR1: ffffffff8fb0bce9 DR2: ffffffff8fb0bcea DR3: ffffffff8fb0bceb DR6: 00000000fffe0ff0 DR7: 0000000000000600 PKRU: 55555554 Call Trace: <TASK> ? die_addr+0x3d/0xa0 ? exc_general_protection+0x144/0x220 ? asm_exc_general_protection+0x22/0x30 ? __kobject_del+0x62/0x1c0 kobject_del+0x32/0x50 parent_remove_sysfs_files+0xd6/0x170 [mdev] mdev_unregister_parent+0xfb/0x190 [mdev] ? mdev_register_parent+0x270/0x270 [mdev] ? find_module_all+0x9d/0xe0 mdpy_dev_exit+0x17/0x63 [mdpy] __do_sys_delete_module.constprop.0+0x2fa/0x4b0 ? module_flags+0x300/0x300 ? __fput+0x4e7/0xa00 do_syscall_64+0x35/0x80 entry_SYSCALL_64_after_hwframe+0x46/0xb0 RIP: 0033:0x7fbc813221b7 Code: 73 01 c3 48 8b 0d d1 8c 2c 00 f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 b8 b0 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d a1 8c 2c 00 f7 d8 64 89 01 48 RSP: 002b:00007ffe780e0648 EFLAGS: 00000206 ORIG_RAX: 00000000000000b0 RAX: ffffffffffffffda RBX: 00007ffe780e06a8 RCX: 00007fbc813221b7 RDX: 000000000000000a RSI: 0000000000000800 RDI: 000055e214df9b58 RBP: 000055e214df9af0 R08: 00007ffe780df5c1 R09: 0000000000000000 R10: 00007fbc8139ecc0 R11: 0000000000000206 R12: 00007ffe780e0870 R13: 00007ffe780e0ed0 R14: 000055e214df9260 R15: 000055e214df9af0 </TASK> Modules linked in: mdpy(-) mdev vfio_iommu_type1 vfio [last unloaded: mdpy] Dumping ftrace buffer: (ftrace buffer empty) ---[ end trace 0000000000000000 ]--- RIP: 0010:__kobject_del+0x62/0x1c0 Code: 48 89 fa 48 c1 ea 03 80 3c 02 00 0f 85 51 01 00 00 48 b8 00 00 00 00 00 fc ff df 48 8b 6b 28 48 8d 7d 10 48 89 fa 48 c1 ea 03 <80> 3c 02 00 0f 85 24 01 00 00 48 8b 75 10 48 89 df 48 8d 6b 3c e8 RSP: 0018:ffff88810695fd30 EFLAGS: 00010202 RAX: dffffc0000000000 RBX: ffffffffa0270268 RCX: 0000000000000000 RDX: 0000000000000002 RSI: 0000000000000004 RDI: 0000000000000010 RBP: 0000000000000000 R08: 0000000000000001 R09: ffffed10233a4ef1 R10: ffff888119d2778b R11: 0000000063666572 R12: 0000000000000000 R13: fffffbfff404e2d4 R14: dffffc0000000000 R15: ffffffffa0271660 FS: 00007fbc81981540(0000) GS:ffff888119d00000(000 ---truncated---

Source: BSI CSAF, BSI WID Portal, ENISA EUVD, NVD (NIST), cvelistv5

Affected products

The following versions are affected. Older releases of the same product line are also vulnerable unless stated otherwise.

Affected products
		Affected versions	Fixed in
Linux	Linux	`6.2 – < 6.5.6` `6.1 – < 6.1.56` `—`	`6.5.6` `6.1.56` `6.6`

Vendors and products

Affected operating systems

Affected operating systems

Linux	linux	linux_kernel	`6.6`
Linux	linux	linux_kernel	—

References & sources

git.kernel.orgstable/c/c01b2e0ee22ef8b4dd7509a93aecc0ac0826bae4euvd, Patch
git.kernel.orgstable/c/52093779b1830ac184a23848d971f06404cf513eeuvd, Patch
git.kernel.orgstable/c/c777b11d34e0f47dbbc4b018ef65ad030f2b283aeuvd, Patch

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