CVE-2023-53566: linux kernel Null Dereference — Fix

Description

In the Linux kernel, the following vulnerability has been resolved: netfilter: nft_set_rbtree: fix null deref on element insertion There is no guarantee that rb_prev() will not return NULL in nft_rbtree_gc_elem(): general protection fault, probably for non-canonical address 0xdffffc0000000003: 0000 [#1] PREEMPT SMP KASAN KASAN: null-ptr-deref in range [0x0000000000000018-0x000000000000001f] nft_add_set_elem+0x14b0/0x2990 nf_tables_newsetelem+0x528/0xb30 Furthermore, there is a possible use-after-free while iterating, 'node' can be free'd so we need to cache the next value to use.

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CVSS v3.1 Score

5.5

MEDIUM

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

Weakness Type (CWE)

CWE-476 CWE-476

Affected Products

Vendor	Product	Versions
linux	linux_kernel	5.10.166 — 5.10.181
linux	linux_kernel	5.15.91 — 5.15.113
linux	linux_kernel	6.1.9 — 6.1.30
linux	linux_kernel	6.2.1 — 6.3.4
linux	linux_kernel	All
linux	linux_kernel	All
linux	linux_kernel	All
linux	linux_kernel	All
linux	linux_kernel	All
linux	linux_kernel	All

References

Advisories & Patches

https://git.kernel.org/stable/c/3fa13203b6d90cc3a33af47b058739f92ab82eef https://git.kernel.org/stable/c/61ae320a29b0540c16931816299eb86bf2b66c08 https://git.kernel.org/stable/c/899aa5638568abf5d69de7a7bb95e4615157375b https://git.kernel.org/stable/c/a337706c1fb35aac3f26b48aca80421bdbe1d33a https://git.kernel.org/stable/c/a836be60a3aabcedcd9c79f545d409ace1f20ba6 https://git.kernel.org/stable/c/b76db53ee8802ee5683f8cb401d7e2ec6f9b3d56 https://git.kernel.org/stable/c/ec5caa765f7f6960011c919c9aeb1467940421f6

Frequently Asked Questions

What is CVE-2023-53566? +

In the Linux kernel, the following vulnerability has been resolved: netfilter: nft_set_rbtree: fix null deref on element insertion There is no guarantee that rb_prev() will not return NULL in nft_rbtree_gc_elem(): general protection fault, probably for non-canonical address 0xdffffc0000000003: 0000 [#1] PREEMPT SMP KASAN KASAN: null-ptr-deref in range [0x0000000000000018-0x000000000000001f] nft_add_set_elem+0x14b0/0x2990 nf_tables_newsetelem+0x528/0xb30 Furthermore, there is a possible use-after-free while iterating, 'node' can be free'd so we need to cache the next value to use. It has a CVSS v3.1 base score of 5.5 (MEDIUM).

How severe is CVE-2023-53566? +

CVE-2023-53566 has a CVSS v3.1 score of 5.5 out of 10, rated MEDIUM. This is a medium-severity vulnerability that should be remediated as part of regular maintenance.

What products are affected by CVE-2023-53566? +

CVE-2023-53566 affects products from linux, specifically: linux_kernel. Check the affected products table above for specific version ranges.

How do I check if I'm vulnerable to CVE-2023-53566? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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CVE-2023-53566