# CVE-2023-53108: net/iucv: Fix size of interrupt data > A buffer overflow in the Linux kernel's IUCV driver allows the z/VM hypervisor to overwrite memory, potentially causing a system crash. - **Severity:** Medium 5.5 (`CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/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:** 2 May 2025 - **Updated:** 11 May 2026 - **Also known as:** BELL-CVE-2023-53108, DEBIAN-CVE-2023-53108, GHSA-phj2-hh6g-c95p, UBUNTU-CVE-2023-53108 ## What is CVE-2023-53108? CVE-2023-53108 is a medium-severity memory corruption vulnerability in Linux kernel, published on 2 May 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: net/iucv: Fix size of interrupt data iucv_irq_data needs to be 4 bytes larger. These bytes are not used by the iucv module, but written by the z/VM hypervisor in case a CPU is deconfigured. Reported as: BUG dma-kmalloc-64 (Not tainted): kmalloc Redzone overwritten ----------------------------------------------------------------------------- 0x0000000000400564-0x0000000000400567 @offset=1380. First byte 0x80 instead of 0xcc Allocated in iucv_cpu_prepare+0x44/0xd0 age=167839 cpu=2 pid=1 __kmem_cache_alloc_node+0x166/0x450 kmalloc_node_trace+0x3a/0x70 iucv_cpu_prepare+0x44/0xd0 cpuhp_invoke_callback+0x156/0x2f0 cpuhp_issue_call+0xf0/0x298 __cpuhp_setup_state_cpuslocked+0x136/0x338 __cpuhp_setup_state+0xf4/0x288 iucv_init+0xf4/0x280 do_one_initcall+0x78/0x390 do_initcalls+0x11a/0x140 kernel_init_freeable+0x25e/0x2a0 kernel_init+0x2e/0x170 __ret_from_fork+0x3c/0x58 ret_from_fork+0xa/0x40 Freed in iucv_init+0x92/0x280 age=167839 cpu=2 pid=1 __kmem_cache_free+0x308/0x358 iucv_init+0x92/0x280 do_one_initcall+0x78/0x390 do_initcalls+0x11a/0x140 kernel_init_freeable+0x25e/0x2a0 kernel_init+0x2e/0x170 __ret_from_fork+0x3c/0x58 ret_from_fork+0xa/0x40 Slab 0x0000037200010000 objects=32 used=30 fp=0x0000000000400640 flags=0x1ffff00000010200(slab|head|node=0|zone=0| Object 0x0000000000400540 @offset=1344 fp=0x0000000000000000 Redzone 0000000000400500: cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc ................ Redzone 0000000000400510: cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc ................ Redzone 0000000000400520: cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc ................ Redzone 0000000000400530: cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc ................ Object 0000000000400540: 00 01 00 03 00 00 00 00 00 00 00 00 00 00 00 00 ................ Object 0000000000400550: f3 86 81 f2 f4 82 f8 82 f0 f0 f0 f0 f0 f0 f0 f2 ................ Object 0000000000400560: 00 00 00 00 80 00 00 00 cc cc cc cc cc cc cc cc ................ Object 0000000000400570: cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc ................ Redzone 0000000000400580: cc cc cc cc cc cc cc cc ........ Padding 00000000004005d4: 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a ZZZZZZZZZZZZZZZZ Padding 00000000004005e4: 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a ZZZZZZZZZZZZZZZZ Padding 00000000004005f4: 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a ZZZZZZZZZZZZ CPU: 6 PID: 121030 Comm: 116-pai-crypto. Not tainted 6.3.0-20230221.rc0.git4.99b8246b2d71.300.fc37.s390x+debug #1 Hardware name: IBM 3931 A01 704 (z/VM 7.3.0) Call Trace: [<000000032aa034ec>] dump_stack_lvl+0xac/0x100 [<0000000329f5a6cc>] check_bytes_and_report+0x104/0x140 [<0000000329f5aa78>] check_object+0x370/0x3c0 [<0000000329f5ede6>] free_debug_processing+0x15e/0x348 [<0000000329f5f06a>] free_to_partial_list+0x9a/0x2f0 [<0000000329f5f4a4>] __slab_free+0x1e4/0x3a8 [<0000000329f61768>] __kmem_cache_free+0x308/0x358 [<000000032a91465c>] iucv_cpu_dead+0x6c/0x88 [<0000000329c2fc66>] cpuhp_invoke_callback+0x156/0x2f0 [<000000032aa062da>] _cpu_down.constprop.0+0x22a/0x5e0 [<0000000329c3243e>] cpu_device_down+0x4e/0x78 [<000000032a61dee0>] device_offline+0xc8/0x118 [<000000032a61e048>] online_store+0x60/0xe0 [<000000032a08b6b0>] kernfs_fop_write_iter+0x150/0x1e8 [<0000000329fab65c>] vfs_write+0x174/0x360 [<0000000329fab9fc>] ksys_write+0x74/0x100 [<000000032aa03a5a>] __do_syscall+0x1da/0x208 [<000000032aa177b2>] system_call+0x82/0xb0 INFO: lockdep is turned off. FIX dma-kmalloc-64: Restoring kmalloc Redzone 0x0000000000400564-0x0000000000400567=0xcc FIX dma-kmalloc-64: Object at 0x0000000000400540 not freed ## Which versions are affected by CVE-2023-53108? It affects 1 product. Products: Linux kernel. ## How do I fix CVE-2023-53108? Apply the vendor's patch. ## Is CVE-2023-53108 being exploited? There is no known exploitation of CVE-2023-53108 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-2023-53108 and fix it if it is affected. What it is: CVE-2023-53108 is a medium-severity memory corruption vulnerability in Linux kernel, published on 2 May 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-2023-53108 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-2023-53108/ (Markdown: https://insights.sbomify.com/CVE-2023-53108/index.md) ``` ## Sources - CVE record: https://www.cve.org/CVERecord?id=CVE-2023-53108 - NVD: https://nvd.nist.gov/vuln/detail/CVE-2023-53108 - OSV: https://osv.dev/vulnerability/CVE-2023-53108 --- From sbomify Insights: https://insights.sbomify.com/CVE-2023-53108/ Summaries are generated and may contain mistakes; the official description above is the record.