# CVE-2022-49395: um: Fix out-of-bounds read in LDT setup > An out-of-bounds read in the Linux kernel UML LDT setup can cause a crash or leak stack memory. - **Severity:** High 7.1 (`CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/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:** 26 Feb 2025 - **Updated:** 11 May 2026 - **Also known as:** ALSA-2025:8743, ALSA-2025:8744, DEBIAN-CVE-2022-49395, GHSA-pxwr-cc58-gq3m, RHSA-2025:8743, RHSA-2025:8744, RLSA-2025:8743, RLSA-2025:8744, UBUNTU-CVE-2022-49395 ## What is CVE-2022-49395? CVE-2022-49395 is a high-severity memory corruption vulnerability in Linux kernel, published on 26 Feb 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: um: Fix out-of-bounds read in LDT setup syscall_stub_data() expects the data_count parameter to be the number of longs, not bytes. ================================================================== BUG: KASAN: stack-out-of-bounds in syscall_stub_data+0x70/0xe0 Read of size 128 at addr 000000006411f6f0 by task swapper/1 CPU: 0 PID: 1 Comm: swapper Not tainted 5.18.0+ #18 Call Trace: show_stack.cold+0x166/0x2a7 __dump_stack+0x3a/0x43 dump_stack_lvl+0x1f/0x27 print_report.cold+0xdb/0xf81 kasan_report+0x119/0x1f0 kasan_check_range+0x3a3/0x440 memcpy+0x52/0x140 syscall_stub_data+0x70/0xe0 write_ldt_entry+0xac/0x190 init_new_ldt+0x515/0x960 init_new_context+0x2c4/0x4d0 mm_init.constprop.0+0x5ed/0x760 mm_alloc+0x118/0x170 0x60033f48 do_one_initcall+0x1d7/0x860 0x60003e7b kernel_init+0x6e/0x3d4 new_thread_handler+0x1e7/0x2c0 The buggy address belongs to stack of task swapper/1 and is located at offset 64 in frame: init_new_ldt+0x0/0x960 This frame has 2 objects: [32, 40) 'addr' [64, 80) 'desc' ================================================================== Weakness: CWE-125 (Out-of-bounds Read) ## Which versions are affected by CVE-2022-49395? It affects 1 product. | Package | Ecosystem | Affected | Fixed in | | --- | --- | --- | --- | | `bpftool` | AlmaLinux:8 | All versions | 4.18.0-553.56.1.el8_10 | | `kernel` | AlmaLinux:8 | All versions | 4.18.0-553.56.1.el8_10 | | `kernel-abi-stablelists` | AlmaLinux:8 | All versions | 4.18.0-553.56.1.el8_10 | | `kernel-core` | AlmaLinux:8 | All versions | 4.18.0-553.56.1.el8_10 | | `kernel-cross-headers` | AlmaLinux:8 | All versions | 4.18.0-553.56.1.el8_10 | | `kernel-debug` | AlmaLinux:8 | All versions | 4.18.0-553.56.1.el8_10 | | `kernel-debug-core` | AlmaLinux:8 | All versions | 4.18.0-553.56.1.el8_10 | | `kernel-debug-devel` | AlmaLinux:8 | All versions | 4.18.0-553.56.1.el8_10 | | `kernel-debug-modules` | AlmaLinux:8 | All versions | 4.18.0-553.56.1.el8_10 | | `kernel-debug-modules-extra` | AlmaLinux:8 | All versions | 4.18.0-553.56.1.el8_10 | | `kernel-devel` | AlmaLinux:8 | All versions | 4.18.0-553.56.1.el8_10 | | `kernel-doc` | AlmaLinux:8 | All versions | 4.18.0-553.56.1.el8_10 | | `kernel-headers` | AlmaLinux:8 | All versions | 4.18.0-553.56.1.el8_10 | | `kernel-modules` | AlmaLinux:8 | All versions | 4.18.0-553.56.1.el8_10 | | `kernel-modules-extra` | AlmaLinux:8 | All versions | 4.18.0-553.56.1.el8_10 | | `kernel-rt` | AlmaLinux:8 | All versions | 4.18.0-553.56.1.rt7.397.el8_10 | | `kernel-rt-core` | AlmaLinux:8 | All versions | 4.18.0-553.56.1.rt7.397.el8_10 | | `kernel-rt-debug` | AlmaLinux:8 | All versions | 4.18.0-553.56.1.rt7.397.el8_10 | | `kernel-rt-debug-core` | AlmaLinux:8 | All versions | 4.18.0-553.56.1.rt7.397.el8_10 | | `kernel-rt-debug-devel` | AlmaLinux:8 | All versions | 4.18.0-553.56.1.rt7.397.el8_10 | | `kernel-rt-debug-modules` | AlmaLinux:8 | All versions | 4.18.0-553.56.1.rt7.397.el8_10 | | `kernel-rt-debug-modules-extra` | AlmaLinux:8 | All versions | 4.18.0-553.56.1.rt7.397.el8_10 | | `kernel-rt-devel` | AlmaLinux:8 | All versions | 4.18.0-553.56.1.rt7.397.el8_10 | | `kernel-rt-modules` | AlmaLinux:8 | All versions | 4.18.0-553.56.1.rt7.397.el8_10 | | `kernel-rt-modules-extra` | AlmaLinux:8 | All versions | 4.18.0-553.56.1.rt7.397.el8_10 | | `kernel-tools` | AlmaLinux:8 | All versions | 4.18.0-553.56.1.el8_10 | | `kernel-tools-libs` | AlmaLinux:8 | All versions | 4.18.0-553.56.1.el8_10 | | `kernel-tools-libs-devel` | AlmaLinux:8 | All versions | 4.18.0-553.56.1.el8_10 | | `kernel-zfcpdump` | AlmaLinux:8 | All versions | 4.18.0-553.56.1.el8_10 | | `kernel-zfcpdump-core` | AlmaLinux:8 | All versions | 4.18.0-553.56.1.el8_10 | | `kernel-zfcpdump-devel` | AlmaLinux:8 | All versions | 4.18.0-553.56.1.el8_10 | | `kernel-zfcpdump-modules` | AlmaLinux:8 | All versions | 4.18.0-553.56.1.el8_10 | | `kernel-zfcpdump-modules-extra` | AlmaLinux:8 | All versions | 4.18.0-553.56.1.el8_10 | | `perf` | AlmaLinux:8 | All versions | 4.18.0-553.56.1.el8_10 | | `python3-perf` | AlmaLinux:8 | All versions | 4.18.0-553.56.1.el8_10 | | `bpftool` | Red Hat:enterprise_linux:8::baseos | All versions | 0:4.18.0-553.56.1.el8_10 | | `bpftool-debuginfo` | Red Hat:enterprise_linux:8::baseos | All versions | 0:4.18.0-553.56.1.el8_10 | | `kernel` | Red Hat:enterprise_linux:8::baseos | All versions | 0:4.18.0-553.56.1.el8_10 | | `kernel-abi-stablelists` | Red Hat:enterprise_linux:8::baseos | All versions | 0:4.18.0-553.56.1.el8_10 | | `kernel-core` | Red Hat:enterprise_linux:8::baseos | All versions | 0:4.18.0-553.56.1.el8_10 | Products: Linux kernel. ## How do I fix CVE-2022-49395? Apply the vendor's patch. ## Is CVE-2022-49395 being exploited? There is no known exploitation of CVE-2022-49395 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-2022-49395 and fix it if it is affected. What it is: CVE-2022-49395 is a high-severity memory corruption vulnerability in Linux kernel, published on 26 Feb 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-2022-49395 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-2022-49395/ (Markdown: https://insights.sbomify.com/CVE-2022-49395/index.md) ``` ## Sources - CVE record: https://www.cve.org/CVERecord?id=CVE-2022-49395 - NVD: https://nvd.nist.gov/vuln/detail/CVE-2022-49395 - OSV: https://osv.dev/vulnerability/CVE-2022-49395 --- From sbomify Insights: https://insights.sbomify.com/CVE-2022-49395/ Summaries are generated and may contain mistakes; the official description above is the record.