# CVE-2019-3900: Denial of service in Kernel > A guest user can cause a denial of service by triggering an infinite loop in the vhost_net kernel module when packet processing is imbalanced. - **Severity:** Medium 6.3 (`CVSS:3.0/AV:N/AC:H/PR:L/UI:N/S:C/C:N/I:N/A:H`) - **Exploited in the wild:** Not known - **Login needed:** Any signed-in user - **Attackable:** Over the internet - **Victim action needed:** Not needed - **Fix available:** Yes - **Published:** 25 Apr 2019 - **Updated:** 4 Aug 2024 - **Also known as:** DEBIAN-CVE-2019-3900, GHSA-h25g-v6rp-rj4h, RHSA-2019:1973, UBUNTU-CVE-2019-3900 ## What is CVE-2019-3900? CVE-2019-3900 is a medium-severity denial of service vulnerability in Canonical Ubuntu Linux, published on 25 Apr 2019. Any signed-in user can exploit it over the network, with no action from the victim. ### Official description An infinite loop issue was found in the vhost_net kernel module in Linux Kernel up to and including v5.1-rc6, while handling incoming packets in handle_rx(). It could occur if one end sends packets faster than the other end can process them. A guest user, maybe remote one, could use this flaw to stall the vhost_net kernel thread, resulting in a DoS scenario. Weakness: CWE-835 (Loop with Unreachable Exit Condition) ## Which versions are affected by CVE-2019-3900? It affects 14 products. | Package | Ecosystem | Affected | Fixed in | | --- | --- | --- | --- | | `kernel` | Red Hat:enterprise_linux:7::server | All versions | 0:4.14.0-115.10.1.el7a | | `kernel-abi-whitelists` | Red Hat:enterprise_linux:7::server | All versions | 0:4.14.0-115.10.1.el7a | | `kernel-alt` | Red Hat:enterprise_linux:7::server | All versions | 0:4.14.0-115.10.1.el7a | | `kernel-bootwrapper` | Red Hat:enterprise_linux:7::server | All versions | 0:4.14.0-115.10.1.el7a | | `kernel-debug` | Red Hat:enterprise_linux:7::server | All versions | 0:4.14.0-115.10.1.el7a | | `kernel-debug-debuginfo` | Red Hat:enterprise_linux:7::server | All versions | 0:4.14.0-115.10.1.el7a | | `kernel-debug-devel` | Red Hat:enterprise_linux:7::server | All versions | 0:4.14.0-115.10.1.el7a | | `kernel-debuginfo` | Red Hat:enterprise_linux:7::server | All versions | 0:4.14.0-115.10.1.el7a | | `kernel-debuginfo-common-ppc64le` | Red Hat:enterprise_linux:7::server | All versions | 0:4.14.0-115.10.1.el7a | | `kernel-devel` | Red Hat:enterprise_linux:7::server | All versions | 0:4.14.0-115.10.1.el7a | | `kernel-doc` | Red Hat:enterprise_linux:7::server | All versions | 0:4.14.0-115.10.1.el7a | | `kernel-headers` | Red Hat:enterprise_linux:7::server | All versions | 0:4.14.0-115.10.1.el7a | | `kernel-tools` | Red Hat:enterprise_linux:7::server | All versions | 0:4.14.0-115.10.1.el7a | | `kernel-tools-debuginfo` | Red Hat:enterprise_linux:7::server | All versions | 0:4.14.0-115.10.1.el7a | | `kernel-tools-libs` | Red Hat:enterprise_linux:7::server | All versions | 0:4.14.0-115.10.1.el7a | | `kernel-tools-libs-devel` | Red Hat:enterprise_linux:7::server | All versions | 0:4.14.0-115.10.1.el7a | | `perf` | Red Hat:enterprise_linux:7::server | All versions | 0:4.14.0-115.10.1.el7a | | `perf-debuginfo` | Red Hat:enterprise_linux:7::server | All versions | 0:4.14.0-115.10.1.el7a | | `python-perf` | Red Hat:enterprise_linux:7::server | All versions | 0:4.14.0-115.10.1.el7a | | `python-perf-debuginfo` | Red Hat:enterprise_linux:7::server | All versions | 0:4.14.0-115.10.1.el7a | Products: Canonical Ubuntu Linux, Debian Debian Linux, Fedoraproject Fedora, Linux kernel, Netapp Active Iq Unified Manager for Vmware Vsphere, Netapp Cn1610 Firmware, Netapp Hci Management Node, Netapp Snapprotect, Netapp Solidfire, Netapp Storage Replication Adapter for Clustered Data Ontap for Vmware Vsphere, Netapp Vasa Provider for Clustered Data Ontap, Netapp Virtual Storage Console for Vmware Vsphere, Oracle Sd-Wan Edge, Redhat Enterprise Linux. ## How do I fix CVE-2019-3900? Apply the vendor's patch. ## Is CVE-2019-3900 being exploited? There is no known exploitation of CVE-2019-3900 in the wild and no public exploit code. ## Other vulnerabilities in Canonical Ubuntu Linux - [CVE-2020-11651](https://insights.sbomify.com/CVE-2020-11651/): SaltStack Salt Authentication Bypass (critical 9.8, exploited in the wild) - [CVE-2020-7247](https://insights.sbomify.com/CVE-2020-7247/): OpenSMTPD Remote Code Execution (critical 9.8, exploited in the wild) - [CVE-2019-16928](https://insights.sbomify.com/CVE-2019-16928/): Exim Out-of-bounds Write (critical 9.8, exploited in the wild) - [CVE-2018-6789](https://insights.sbomify.com/CVE-2018-6789/): Exim Buffer Overflow (critical 9.8, exploited in the wild) - [CVE-2015-2590](https://insights.sbomify.com/CVE-2015-2590/): Oracle Java SE and Java SE Embedded Remote Code Execution (critical 9.8, exploited in the wild) ## Fix prompt for AI coding agents ```text Check this codebase for CVE-2019-3900 and fix it if it is affected. What it is: CVE-2019-3900 is a medium-severity denial of service vulnerability in Canonical Ubuntu Linux, published on 25 Apr 2019. Any signed-in user can exploit it over the network, with no action from the victim. Exploitation: There is no known exploitation of CVE-2019-3900 in the wild and no public exploit code. Affected product: Canonical Ubuntu Linux. 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-2019-3900/ (Markdown: https://insights.sbomify.com/CVE-2019-3900/index.md) ``` ## Sources - CVE record: https://www.cve.org/CVERecord?id=CVE-2019-3900 - NVD: https://nvd.nist.gov/vuln/detail/CVE-2019-3900 - OSV: https://osv.dev/vulnerability/CVE-2019-3900 --- From sbomify Insights: https://insights.sbomify.com/CVE-2019-3900/ Summaries are generated and may contain mistakes; the official description above is the record.