# CVE-2016-4470: Null dereference in n/a > Local attackers can crash the system via a crafted keyctl request due to uninitialized data structures in the Linux kernel key management subsystem. - **Severity:** Medium 5.5 (`CVSS:3.0/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:** 27 Jun 2016 - **Updated:** 6 Aug 2024 - **Also known as:** DEBIAN-CVE-2016-4470, GHSA-9x7c-6h5w-qmpg, RHSA-2016:2074, RHSA-2016:2076, SUSE-SU-2016:1998-1, SUSE-SU-2016:1999-1, UBUNTU-CVE-2016-4470 ## What is CVE-2016-4470? CVE-2016-4470 is a medium-severity vulnerability in Linux kernel, published on 27 Jun 2016. It can only be exploited from the same machine or local network, with no action from the victim. ### Official description The key_reject_and_link function in security/keys/key.c in the Linux kernel through 4.6.3 does not ensure that a certain data structure is initialized, which allows local users to cause a denial of service (system crash) via vectors involving a crafted keyctl request2 command. ## Which versions are affected by CVE-2016-4470? It affects 14 products. | Package | Ecosystem | Affected | Fixed in | | --- | --- | --- | --- | | `kernel` | Red Hat:rhel_aus:6.5::server | All versions | 0:2.6.32-431.74.1.el6 | | `kernel-abi-whitelists` | Red Hat:rhel_aus:6.5::server | All versions | 0:2.6.32-431.74.1.el6 | | `kernel-debug` | Red Hat:rhel_aus:6.5::server | All versions | 0:2.6.32-431.74.1.el6 | | `kernel-debug-debuginfo` | Red Hat:rhel_aus:6.5::server | All versions | 0:2.6.32-431.74.1.el6 | | `kernel-debug-devel` | Red Hat:rhel_aus:6.5::server | All versions | 0:2.6.32-431.74.1.el6 | | `kernel-debuginfo` | Red Hat:rhel_aus:6.5::server | All versions | 0:2.6.32-431.74.1.el6 | | `kernel-debuginfo-common-x86_64` | Red Hat:rhel_aus:6.5::server | All versions | 0:2.6.32-431.74.1.el6 | | `kernel-devel` | Red Hat:rhel_aus:6.5::server | All versions | 0:2.6.32-431.74.1.el6 | | `kernel-doc` | Red Hat:rhel_aus:6.5::server | All versions | 0:2.6.32-431.74.1.el6 | | `kernel-firmware` | Red Hat:rhel_aus:6.5::server | All versions | 0:2.6.32-431.74.1.el6 | | `kernel-headers` | Red Hat:rhel_aus:6.5::server | All versions | 0:2.6.32-431.74.1.el6 | | `perf` | Red Hat:rhel_aus:6.5::server | All versions | 0:2.6.32-431.74.1.el6 | | `perf-debuginfo` | Red Hat:rhel_aus:6.5::server | All versions | 0:2.6.32-431.74.1.el6 | | `python-perf` | Red Hat:rhel_aus:6.5::server | All versions | 0:2.6.32-431.74.1.el6 | | `python-perf-debuginfo` | Red Hat:rhel_aus:6.5::server | All versions | 0:2.6.32-431.74.1.el6 | | `kernel` | Red Hat:rhel_eus:6.7::computenode | All versions | 0:2.6.32-573.35.1.el6 | | `kernel-abi-whitelists` | Red Hat:rhel_eus:6.7::computenode | All versions | 0:2.6.32-573.35.1.el6 | | `kernel-debug` | Red Hat:rhel_eus:6.7::computenode | All versions | 0:2.6.32-573.35.1.el6 | | `kernel-debug-debuginfo` | Red Hat:rhel_eus:6.7::computenode | All versions | 0:2.6.32-573.35.1.el6 | | `kernel-debug-devel` | Red Hat:rhel_eus:6.7::computenode | All versions | 0:2.6.32-573.35.1.el6 | | `kernel-debuginfo` | Red Hat:rhel_eus:6.7::computenode | All versions | 0:2.6.32-573.35.1.el6 | | `kernel-debuginfo-common-i686` | Red Hat:rhel_eus:6.7::computenode | All versions | 0:2.6.32-573.35.1.el6 | | `kernel-debuginfo-common-x86_64` | Red Hat:rhel_eus:6.7::computenode | All versions | 0:2.6.32-573.35.1.el6 | | `kernel-devel` | Red Hat:rhel_eus:6.7::computenode | All versions | 0:2.6.32-573.35.1.el6 | | `kernel-doc` | Red Hat:rhel_eus:6.7::computenode | All versions | 0:2.6.32-573.35.1.el6 | | `kernel-firmware` | Red Hat:rhel_eus:6.7::computenode | All versions | 0:2.6.32-573.35.1.el6 | | `kernel-headers` | Red Hat:rhel_eus:6.7::computenode | All versions | 0:2.6.32-573.35.1.el6 | | `perf` | Red Hat:rhel_eus:6.7::computenode | All versions | 0:2.6.32-573.35.1.el6 | | `perf-debuginfo` | Red Hat:rhel_eus:6.7::computenode | All versions | 0:2.6.32-573.35.1.el6 | | `python-perf` | Red Hat:rhel_eus:6.7::computenode | All versions | 0:2.6.32-573.35.1.el6 | | `python-perf-debuginfo` | Red Hat:rhel_eus:6.7::computenode | All versions | 0:2.6.32-573.35.1.el6 | | `kernel` | Red Hat:rhel_eus:6.7::server | All versions | 0:2.6.32-573.35.1.el6 | | `kernel-abi-whitelists` | Red Hat:rhel_eus:6.7::server | All versions | 0:2.6.32-573.35.1.el6 | | `kernel-bootwrapper` | Red Hat:rhel_eus:6.7::server | All versions | 0:2.6.32-573.35.1.el6 | | `kernel-debug` | Red Hat:rhel_eus:6.7::server | All versions | 0:2.6.32-573.35.1.el6 | | `kernel-debug-debuginfo` | Red Hat:rhel_eus:6.7::server | All versions | 0:2.6.32-573.35.1.el6 | | `kernel-debug-devel` | Red Hat:rhel_eus:6.7::server | All versions | 0:2.6.32-573.35.1.el6 | | `kernel-debuginfo` | Red Hat:rhel_eus:6.7::server | All versions | 0:2.6.32-573.35.1.el6 | | `kernel-debuginfo-common-i686` | Red Hat:rhel_eus:6.7::server | All versions | 0:2.6.32-573.35.1.el6 | | `kernel-debuginfo-common-ppc64` | Red Hat:rhel_eus:6.7::server | All versions | 0:2.6.32-573.35.1.el6 | Products: Linux kernel, Novell Suse Linux Enterprise Real Time Extension, Oracle Linux, Oracle Vm Server, Redhat Enterprise Linux, Redhat Enterprise Linux Desktop, Redhat Enterprise Linux for Real Time, Redhat Enterprise Linux Hpc Node, Redhat Enterprise Linux Hpc Node Eus, Redhat Enterprise Linux Server, Redhat Enterprise Linux Server Aus, Redhat Enterprise Linux Server Eus, Redhat Enterprise Linux Workstation, Redhat Enterprise Mrg. ## How do I fix CVE-2016-4470? Apply the vendor's patch. ## Is CVE-2016-4470 being exploited? There is no known exploitation of CVE-2016-4470 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-2016-4470 and fix it if it is affected. What it is: CVE-2016-4470 is a medium-severity vulnerability in Linux kernel, published on 27 Jun 2016. 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-2016-4470 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-2016-4470/ (Markdown: https://insights.sbomify.com/CVE-2016-4470/index.md) ``` ## Sources - CVE record: https://www.cve.org/CVERecord?id=CVE-2016-4470 - NVD: https://nvd.nist.gov/vuln/detail/CVE-2016-4470 - OSV: https://osv.dev/vulnerability/CVE-2016-4470 --- From sbomify Insights: https://insights.sbomify.com/CVE-2016-4470/ Summaries are generated and may contain mistakes; the official description above is the record.