# CVE-2015-4170: Race condition in n/a > Local attackers can cause a denial of service in the Linux kernel by triggering a race condition during TTY thread shutdown. - **Severity:** Medium 4.7 (`CVSS:3.0/AV:L/AC:H/PR:N/UI:R/S:U/C:N/I:N/A:H`) - **Exploited in the wild:** Not known - **Login needed:** Not needed - **Attackable:** Local or same network only - **Victim action needed:** A user has to click or open something - **Fix available:** Yes - **Published:** 2 May 2016 - **Updated:** 6 Aug 2024 - **Also known as:** DEBIAN-CVE-2015-4170, GHSA-mqxq-v3w5-xvj4, RHSA-2016:1395 ## What is CVE-2015-4170? CVE-2015-4170 is a medium-severity vulnerability in Linux kernel, published on 2 May 2016. It can only be exploited from the same machine or local network, and only if a user opens a file or follows a link. ### Official description Race condition in the ldsem_cmpxchg function in drivers/tty/tty_ldsem.c in the Linux kernel before 3.13-rc4-next-20131218 allows local users to cause a denial of service (ldsem_down_read and ldsem_down_write deadlock) by establishing a new tty thread during shutdown of a previous tty thread. Weakness: CWE-362 (Concurrent Execution using Shared Resource with Improper Synchronization) ## Which versions are affected by CVE-2015-4170? It affects 6 products. | Package | Ecosystem | Affected | Fixed in | | --- | --- | --- | --- | | `kernel` | Red Hat:rhel_eus:7.1::computenode | All versions | 0:3.10.0-229.38.1.el7 | | `kernel-abi-whitelists` | Red Hat:rhel_eus:7.1::computenode | All versions | 0:3.10.0-229.38.1.el7 | | `kernel-debug` | Red Hat:rhel_eus:7.1::computenode | All versions | 0:3.10.0-229.38.1.el7 | | `kernel-debug-debuginfo` | Red Hat:rhel_eus:7.1::computenode | All versions | 0:3.10.0-229.38.1.el7 | | `kernel-debug-devel` | Red Hat:rhel_eus:7.1::computenode | All versions | 0:3.10.0-229.38.1.el7 | | `kernel-debuginfo` | Red Hat:rhel_eus:7.1::computenode | All versions | 0:3.10.0-229.38.1.el7 | | `kernel-debuginfo-common-x86_64` | Red Hat:rhel_eus:7.1::computenode | All versions | 0:3.10.0-229.38.1.el7 | | `kernel-devel` | Red Hat:rhel_eus:7.1::computenode | All versions | 0:3.10.0-229.38.1.el7 | | `kernel-doc` | Red Hat:rhel_eus:7.1::computenode | All versions | 0:3.10.0-229.38.1.el7 | | `kernel-headers` | Red Hat:rhel_eus:7.1::computenode | All versions | 0:3.10.0-229.38.1.el7 | | `kernel-tools` | Red Hat:rhel_eus:7.1::computenode | All versions | 0:3.10.0-229.38.1.el7 | | `kernel-tools-debuginfo` | Red Hat:rhel_eus:7.1::computenode | All versions | 0:3.10.0-229.38.1.el7 | | `kernel-tools-libs` | Red Hat:rhel_eus:7.1::computenode | All versions | 0:3.10.0-229.38.1.el7 | | `kernel-tools-libs-devel` | Red Hat:rhel_eus:7.1::computenode | All versions | 0:3.10.0-229.38.1.el7 | | `perf` | Red Hat:rhel_eus:7.1::computenode | All versions | 0:3.10.0-229.38.1.el7 | | `perf-debuginfo` | Red Hat:rhel_eus:7.1::computenode | All versions | 0:3.10.0-229.38.1.el7 | | `python-perf` | Red Hat:rhel_eus:7.1::computenode | All versions | 0:3.10.0-229.38.1.el7 | | `python-perf-debuginfo` | Red Hat:rhel_eus:7.1::computenode | All versions | 0:3.10.0-229.38.1.el7 | | `kernel` | Red Hat:rhel_eus:7.1::server | All versions | 0:3.10.0-229.38.1.ael7b | | `kernel-abi-whitelists` | Red Hat:rhel_eus:7.1::server | All versions | 0:3.10.0-229.38.1.ael7b | | `kernel-bootwrapper` | Red Hat:rhel_eus:7.1::server | All versions | 0:3.10.0-229.38.1.ael7b | | `kernel-debug` | Red Hat:rhel_eus:7.1::server | All versions | 0:3.10.0-229.38.1.ael7b | | `kernel-debug-debuginfo` | Red Hat:rhel_eus:7.1::server | All versions | 0:3.10.0-229.38.1.ael7b | | `kernel-debug-devel` | Red Hat:rhel_eus:7.1::server | All versions | 0:3.10.0-229.38.1.ael7b | | `kernel-debuginfo` | Red Hat:rhel_eus:7.1::server | All versions | 0:3.10.0-229.38.1.ael7b | | `kernel-debuginfo-common-ppc64` | Red Hat:rhel_eus:7.1::server | All versions | 0:3.10.0-229.38.1.el7 | | `kernel-debuginfo-common-ppc64le` | Red Hat:rhel_eus:7.1::server | All versions | 0:3.10.0-229.38.1.ael7b | | `kernel-debuginfo-common-s390x` | Red Hat:rhel_eus:7.1::server | All versions | 0:3.10.0-229.38.1.el7 | | `kernel-debuginfo-common-x86_64` | Red Hat:rhel_eus:7.1::server | All versions | 0:3.10.0-229.38.1.el7 | | `kernel-devel` | Red Hat:rhel_eus:7.1::server | All versions | 0:3.10.0-229.38.1.ael7b | | `kernel-doc` | Red Hat:rhel_eus:7.1::server | All versions | 0:3.10.0-229.38.1.ael7b | | `kernel-headers` | Red Hat:rhel_eus:7.1::server | All versions | 0:3.10.0-229.38.1.ael7b | | `kernel-kdump` | Red Hat:rhel_eus:7.1::server | All versions | 0:3.10.0-229.38.1.el7 | | `kernel-kdump-debuginfo` | Red Hat:rhel_eus:7.1::server | All versions | 0:3.10.0-229.38.1.el7 | | `kernel-kdump-devel` | Red Hat:rhel_eus:7.1::server | All versions | 0:3.10.0-229.38.1.el7 | | `kernel-tools` | Red Hat:rhel_eus:7.1::server | All versions | 0:3.10.0-229.38.1.ael7b | | `kernel-tools-debuginfo` | Red Hat:rhel_eus:7.1::server | All versions | 0:3.10.0-229.38.1.ael7b | | `kernel-tools-libs` | Red Hat:rhel_eus:7.1::server | All versions | 0:3.10.0-229.38.1.ael7b | | `kernel-tools-libs-devel` | Red Hat:rhel_eus:7.1::server | All versions | 0:3.10.0-229.38.1.ael7b | | `perf` | Red Hat:rhel_eus:7.1::server | All versions | 0:3.10.0-229.38.1.ael7b | Products: Linux kernel, Redhat Enterprise Linux Compute Node Eus, Redhat Enterprise Linux for Ibm Z Systems Eus, Redhat Enterprise Linux for Power Big Endian Eus, Redhat Enterprise Linux for Power Little Endian Eus, Redhat Enterprise Linux Server Eus. ## How do I fix CVE-2015-4170? Apply the vendor's patch. ## Is CVE-2015-4170 being exploited? There is no known exploitation of CVE-2015-4170 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-2015-4170 and fix it if it is affected. What it is: CVE-2015-4170 is a medium-severity vulnerability in Linux kernel, published on 2 May 2016. It can only be exploited from the same machine or local network, and only if a user opens a file or follows a link. Exploitation: There is no known exploitation of CVE-2015-4170 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-2015-4170/ (Markdown: https://insights.sbomify.com/CVE-2015-4170/index.md) ``` ## Sources - CVE record: https://www.cve.org/CVERecord?id=CVE-2015-4170 - NVD: https://nvd.nist.gov/vuln/detail/CVE-2015-4170 - OSV: https://osv.dev/vulnerability/CVE-2015-4170 --- From sbomify Insights: https://insights.sbomify.com/CVE-2015-4170/ Summaries are generated and may contain mistakes; the official description above is the record.