# CVE-2023-53217: nubus: Partially revert proc_create_single_data() conversion > A regression in the Linux kernel nubus driver causes a null pointer dereference and kernel crash when reading specific proc files. - **Severity:** High 7.8 (`CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H`) - **Exploited in the wild:** Not known - **Login needed:** Any signed-in user - **Attackable:** Local or same network only - **Victim action needed:** Not needed - **Fix available:** Yes - **Published:** 15 Sep 2025 - **Updated:** 11 May 2026 - **Also known as:** BELL-CVE-2023-53217, DEBIAN-CVE-2023-53217, GHSA-973h-6xgh-w3xj, UBUNTU-CVE-2023-53217 ## What is CVE-2023-53217? CVE-2023-53217 is a high-severity vulnerability in Linux kernel, published on 15 Sep 2025. It can only be exploited from the same machine or local network, with no action from the victim. ### Official description In the Linux kernel, the following vulnerability has been resolved: nubus: Partially revert proc_create_single_data() conversion The conversion to proc_create_single_data() introduced a regression whereby reading a file in /proc/bus/nubus results in a seg fault: # grep -r . /proc/bus/nubus/e/ Data read fault at 0x00000020 in Super Data (pc=0x1074c2) BAD KERNEL BUSERR Oops: 00000000 Modules linked in: PC: [<001074c2>] PDE_DATA+0xc/0x16 SR: 2010 SP: 38284958 a2: 01152370 d0: 00000001 d1: 01013000 d2: 01002790 d3: 00000000 d4: 00000001 d5: 0008ce2e a0: 00000000 a1: 00222a40 Process grep (pid: 45, task=142f8727) Frame format=B ssw=074d isc=2008 isb=4e5e daddr=00000020 dobuf=01199e70 baddr=001074c8 dibuf=ffffffff ver=f Stack from 01199e48: 01199e70 00222a58 01002790 00000000 011a3000 01199eb0 015000c0 00000000 00000000 01199ec0 01199ec0 000d551a 011a3000 00000001 00000000 00018000 d003f000 00000003 00000001 0002800d 01052840 01199fa8 c01f8000 00000000 00000029 0b532b80 00000000 00000000 00000029 0b532b80 01199ee4 00103640 011198c0 d003f000 00018000 01199fa8 00000000 011198c0 00000000 01199f4c 000b3344 011198c0 d003f000 00018000 01199fa8 00000000 00018000 011198c0 Call Trace: [<00222a58>] nubus_proc_rsrc_show+0x18/0xa0 [<000d551a>] seq_read+0xc4/0x510 [<00018000>] fp_fcos+0x2/0x82 [<0002800d>] __sys_setreuid+0x115/0x1c6 [<00103640>] proc_reg_read+0x5c/0xb0 [<00018000>] fp_fcos+0x2/0x82 [<000b3344>] __vfs_read+0x2c/0x13c [<00018000>] fp_fcos+0x2/0x82 [<00018000>] fp_fcos+0x2/0x82 [<000b8aa2>] sys_statx+0x60/0x7e [<000b34b6>] vfs_read+0x62/0x12a [<00018000>] fp_fcos+0x2/0x82 [<00018000>] fp_fcos+0x2/0x82 [<000b39c2>] ksys_read+0x48/0xbe [<00018000>] fp_fcos+0x2/0x82 [<000b3a4e>] sys_read+0x16/0x1a [<00018000>] fp_fcos+0x2/0x82 [<00002b84>] syscall+0x8/0xc [<00018000>] fp_fcos+0x2/0x82 [<0000c016>] not_ext+0xa/0x18 Code: 4e5e 4e75 4e56 0000 206e 0008 2068 ffe8 <2068> 0020 2008 4e5e 4e75 4e56 0000 2f0b 206e 0008 2068 0004 2668 0020 206b ffe8 Disabling lock debugging due to kernel taint Segmentation fault The proc_create_single_data() conversion does not work because single_open(file, nubus_proc_rsrc_show, PDE_DATA(inode)) is not equivalent to the original code. ## Which versions are affected by CVE-2023-53217? It affects 1 product. Products: Linux kernel. ## How do I fix CVE-2023-53217? Apply the vendor's patch. ## Is CVE-2023-53217 being exploited? There is no known exploitation of CVE-2023-53217 in the wild and no public exploit code. ## Other vulnerabilities in Linux kernel - [CVE-2026-53266](https://insights.sbomify.com/CVE-2026-53266/): Linux Kernel Out-of-Bounds Write (high 8.8, exploited in the wild) - [CVE-2013-6282](https://insights.sbomify.com/CVE-2013-6282/): Linux Kernel Improper Input Validation (high 8.8, exploited in the wild) - [CVE-2022-0185](https://insights.sbomify.com/CVE-2022-0185/): Linux Kernel Heap-Based Buffer Overflow (high 8.4, exploited in the wild) - [CVE-2013-2094](https://insights.sbomify.com/CVE-2013-2094/): Linux Kernel Privilege Escalation (high 8.4, exploited in the wild) - [CVE-2026-53362](https://insights.sbomify.com/CVE-2026-53362/): Linux Kernel Unspecified (high 7.8, exploited in the wild) ## Fix prompt for AI coding agents ```text Check this codebase for CVE-2023-53217 and fix it if it is affected. What it is: CVE-2023-53217 is a high-severity vulnerability in Linux kernel, published on 15 Sep 2025. It can only be exploited from the same machine or local network, with no action from the victim. Exploitation: There is no known exploitation of CVE-2023-53217 in the wild and no public exploit code. Affected product: Linux kernel. No package-level version data is available, so check the vendor advisory linked from the reference page. Task: 1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies. 2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it. 3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead. 4. Run the tests and summarise what changed and why. 5. If nothing in the project is affected, say so and change nothing. Reference: https://insights.sbomify.com/CVE-2023-53217/ (Markdown: https://insights.sbomify.com/CVE-2023-53217/index.md) ``` ## Sources - CVE record: https://www.cve.org/CVERecord?id=CVE-2023-53217 - NVD: https://nvd.nist.gov/vuln/detail/CVE-2023-53217 - OSV: https://osv.dev/vulnerability/CVE-2023-53217 --- From sbomify Insights: https://insights.sbomify.com/CVE-2023-53217/ Summaries are generated and may contain mistakes; the official description above is the record.