# CVE-2018-18559: Use after free in n/a > A race condition in the Linux kernel AF_PACKET socket handling allows attackers to achieve program counter control via use-after-free. - **Severity:** High 8.1 (`CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H`) - **Exploited in the wild:** Not known - **Login needed:** Not needed - **Attackable:** Over the internet - **Victim action needed:** Not needed - **Fix available:** Yes - **Published:** 22 Oct 2018 - **Updated:** 5 Aug 2024 - **Also known as:** DEBIAN-CVE-2018-18559, GHSA-8w88-57v8-p48h, RHSA-2019:0188, UBUNTU-CVE-2018-18559 ## What is CVE-2018-18559? CVE-2018-18559 is a high-severity use after free vulnerability in Linux kernel, published on 22 Oct 2018. An attacker can exploit it over the internet without logging in, with no action from the victim. ### Official description In the Linux kernel through 4.19, a use-after-free can occur due to a race condition between fanout_add from setsockopt and bind on an AF_PACKET socket. This issue exists because of the 15fe076edea787807a7cdc168df832544b58eba6 incomplete fix for a race condition. The code mishandles a certain multithreaded case involving a packet_do_bind unregister action followed by a packet_notifier register action. Later, packet_release operates on only one of the two applicable linked lists. The attacker can achieve Program Counter control. Weakness: CWE-416 (Use After Free), CWE-362 (Concurrent Execution using Shared Resource with Improper Synchronization) ## Which versions are affected by CVE-2018-18559? It affects 9 products. | Package | Ecosystem | Affected | Fixed in | | --- | --- | --- | --- | | `kernel-rt` | Red Hat:rhel_extras_rt:7 | All versions | 0:3.10.0-957.5.1.rt56.916.el7 | | `kernel-rt-debug` | Red Hat:rhel_extras_rt:7 | All versions | 0:3.10.0-957.5.1.rt56.916.el7 | | `kernel-rt-debug-debuginfo` | Red Hat:rhel_extras_rt:7 | All versions | 0:3.10.0-957.5.1.rt56.916.el7 | | `kernel-rt-debug-devel` | Red Hat:rhel_extras_rt:7 | All versions | 0:3.10.0-957.5.1.rt56.916.el7 | | `kernel-rt-debug-kvm` | Red Hat:rhel_extras_rt:7 | All versions | 0:3.10.0-957.5.1.rt56.916.el7 | | `kernel-rt-debug-kvm-debuginfo` | Red Hat:rhel_extras_rt:7 | All versions | 0:3.10.0-957.5.1.rt56.916.el7 | | `kernel-rt-debuginfo` | Red Hat:rhel_extras_rt:7 | All versions | 0:3.10.0-957.5.1.rt56.916.el7 | | `kernel-rt-debuginfo-common-x86_64` | Red Hat:rhel_extras_rt:7 | All versions | 0:3.10.0-957.5.1.rt56.916.el7 | | `kernel-rt-devel` | Red Hat:rhel_extras_rt:7 | All versions | 0:3.10.0-957.5.1.rt56.916.el7 | | `kernel-rt-doc` | Red Hat:rhel_extras_rt:7 | All versions | 0:3.10.0-957.5.1.rt56.916.el7 | | `kernel-rt-kvm` | Red Hat:rhel_extras_rt:7 | All versions | 0:3.10.0-957.5.1.rt56.916.el7 | | `kernel-rt-kvm-debuginfo` | Red Hat:rhel_extras_rt:7 | All versions | 0:3.10.0-957.5.1.rt56.916.el7 | | `kernel-rt-trace` | Red Hat:rhel_extras_rt:7 | All versions | 0:3.10.0-957.5.1.rt56.916.el7 | | `kernel-rt-trace-debuginfo` | Red Hat:rhel_extras_rt:7 | All versions | 0:3.10.0-957.5.1.rt56.916.el7 | | `kernel-rt-trace-devel` | Red Hat:rhel_extras_rt:7 | All versions | 0:3.10.0-957.5.1.rt56.916.el7 | | `kernel-rt-trace-kvm` | Red Hat:rhel_extras_rt:7 | All versions | 0:3.10.0-957.5.1.rt56.916.el7 | | `kernel-rt-trace-kvm-debuginfo` | Red Hat:rhel_extras_rt:7 | All versions | 0:3.10.0-957.5.1.rt56.916.el7 | Products: Linux kernel, Redhat Enterprise Linux Desktop, Redhat Enterprise Linux Server, Redhat Enterprise Linux Server Aus, Redhat Enterprise Linux Server Eus, Redhat Enterprise Linux Server Tus, Redhat Enterprise Linux Workstation, Redhat Openshift Container Platform, Redhat Virtualization Host. ## How do I fix CVE-2018-18559? Apply the vendor's patch. ## Is CVE-2018-18559 being exploited? There is no known exploitation of CVE-2018-18559 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-2018-18559 and fix it if it is affected. What it is: CVE-2018-18559 is a high-severity use after free vulnerability in Linux kernel, published on 22 Oct 2018. An attacker can exploit it over the internet without logging in, with no action from the victim. Exploitation: There is no known exploitation of CVE-2018-18559 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-2018-18559/ (Markdown: https://insights.sbomify.com/CVE-2018-18559/index.md) ``` ## Sources - CVE record: https://www.cve.org/CVERecord?id=CVE-2018-18559 - NVD: https://nvd.nist.gov/vuln/detail/CVE-2018-18559 - OSV: https://osv.dev/vulnerability/CVE-2018-18559 --- From sbomify Insights: https://insights.sbomify.com/CVE-2018-18559/ Summaries are generated and may contain mistakes; the official description above is the record.