# CVE-2019-3840: Null dereference in libvirt > A guest VM attacker can crash the libvirt daemon via a NULL pointer dereference in QEMU agent interface handling, causing denial of service. - **Severity:** Medium 5.8 (`CVSS:3.0/AV:N/AC:H/PR:L/UI:R/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:** A user has to click or open something - **Fix available:** Yes - **Published:** 27 Mar 2019 - **Updated:** 4 Aug 2024 - **Also known as:** DEBIAN-CVE-2019-3840, GHSA-rx4m-pcxc-jchp, MGASA-2019-0138, RHSA-2019:2294, SUSE-SU-2019:0553-1, SUSE-SU-2019:0936-1, UBUNTU-CVE-2019-3840, USN-3909-1, openSUSE-SU-2019:1288-1 ## What is CVE-2019-3840? CVE-2019-3840 is a medium-severity vulnerability in Opensuse Leap, published on 27 Mar 2019. Any signed-in user can exploit it over the network, and only if a user opens a file or follows a link. ### Official description A NULL pointer dereference flaw was discovered in libvirt before version 5.0.0 in the way it gets interface information through the QEMU agent. An attacker in a guest VM can use this flaw to crash libvirtd and cause a denial of service. Weakness: CWE-476 (NULL Pointer Dereference) ## Which versions are affected by CVE-2019-3840? It affects 2 products. | Package | Ecosystem | Affected | Fixed in | | --- | --- | --- | --- | | `libvirt` | Red Hat:enterprise_linux:7::client | All versions | 0:4.5.0-23.el7 | | `libvirt-admin` | Red Hat:enterprise_linux:7::client | All versions | 0:4.5.0-23.el7 | | `libvirt-bash-completion` | Red Hat:enterprise_linux:7::client | All versions | 0:4.5.0-23.el7 | | `libvirt-client` | Red Hat:enterprise_linux:7::client | All versions | 0:4.5.0-23.el7 | | `libvirt-daemon` | Red Hat:enterprise_linux:7::client | All versions | 0:4.5.0-23.el7 | | `libvirt-daemon-config-network` | Red Hat:enterprise_linux:7::client | All versions | 0:4.5.0-23.el7 | | `libvirt-daemon-config-nwfilter` | Red Hat:enterprise_linux:7::client | All versions | 0:4.5.0-23.el7 | | `libvirt-daemon-driver-interface` | Red Hat:enterprise_linux:7::client | All versions | 0:4.5.0-23.el7 | | `libvirt-daemon-driver-lxc` | Red Hat:enterprise_linux:7::client | All versions | 0:4.5.0-23.el7 | | `libvirt-daemon-driver-network` | Red Hat:enterprise_linux:7::client | All versions | 0:4.5.0-23.el7 | | `libvirt-daemon-driver-nodedev` | Red Hat:enterprise_linux:7::client | All versions | 0:4.5.0-23.el7 | | `libvirt-daemon-driver-nwfilter` | Red Hat:enterprise_linux:7::client | All versions | 0:4.5.0-23.el7 | | `libvirt-daemon-driver-qemu` | Red Hat:enterprise_linux:7::client | All versions | 0:4.5.0-23.el7 | | `libvirt-daemon-driver-secret` | Red Hat:enterprise_linux:7::client | All versions | 0:4.5.0-23.el7 | | `libvirt-daemon-driver-storage` | Red Hat:enterprise_linux:7::client | All versions | 0:4.5.0-23.el7 | | `libvirt-daemon-driver-storage-core` | Red Hat:enterprise_linux:7::client | All versions | 0:4.5.0-23.el7 | | `libvirt-daemon-driver-storage-disk` | Red Hat:enterprise_linux:7::client | All versions | 0:4.5.0-23.el7 | | `libvirt-daemon-driver-storage-gluster` | Red Hat:enterprise_linux:7::client | All versions | 0:4.5.0-23.el7 | | `libvirt-daemon-driver-storage-iscsi` | Red Hat:enterprise_linux:7::client | All versions | 0:4.5.0-23.el7 | | `libvirt-daemon-driver-storage-logical` | Red Hat:enterprise_linux:7::client | All versions | 0:4.5.0-23.el7 | | `libvirt-daemon-driver-storage-mpath` | Red Hat:enterprise_linux:7::client | All versions | 0:4.5.0-23.el7 | | `libvirt-daemon-driver-storage-rbd` | Red Hat:enterprise_linux:7::client | All versions | 0:4.5.0-23.el7 | | `libvirt-daemon-driver-storage-scsi` | Red Hat:enterprise_linux:7::client | All versions | 0:4.5.0-23.el7 | | `libvirt-daemon-kvm` | Red Hat:enterprise_linux:7::client | All versions | 0:4.5.0-23.el7 | | `libvirt-daemon-lxc` | Red Hat:enterprise_linux:7::client | All versions | 0:4.5.0-23.el7 | | `libvirt-debuginfo` | Red Hat:enterprise_linux:7::client | All versions | 0:4.5.0-23.el7 | | `libvirt-devel` | Red Hat:enterprise_linux:7::client | All versions | 0:4.5.0-23.el7 | | `libvirt-docs` | Red Hat:enterprise_linux:7::client | All versions | 0:4.5.0-23.el7 | | `libvirt-libs` | Red Hat:enterprise_linux:7::client | All versions | 0:4.5.0-23.el7 | | `libvirt-lock-sanlock` | Red Hat:enterprise_linux:7::client | All versions | 0:4.5.0-23.el7 | | `libvirt-login-shell` | Red Hat:enterprise_linux:7::client | All versions | 0:4.5.0-23.el7 | | `libvirt-nss` | Red Hat:enterprise_linux:7::client | All versions | 0:4.5.0-23.el7 | | `libvirt` | Red Hat:enterprise_linux:7::computenode | All versions | 0:4.5.0-23.el7 | | `libvirt-admin` | Red Hat:enterprise_linux:7::computenode | All versions | 0:4.5.0-23.el7 | | `libvirt-bash-completion` | Red Hat:enterprise_linux:7::computenode | All versions | 0:4.5.0-23.el7 | | `libvirt-client` | Red Hat:enterprise_linux:7::computenode | All versions | 0:4.5.0-23.el7 | | `libvirt-daemon` | Red Hat:enterprise_linux:7::computenode | All versions | 0:4.5.0-23.el7 | | `libvirt-daemon-config-network` | Red Hat:enterprise_linux:7::computenode | All versions | 0:4.5.0-23.el7 | | `libvirt-daemon-config-nwfilter` | Red Hat:enterprise_linux:7::computenode | All versions | 0:4.5.0-23.el7 | | `libvirt-daemon-driver-interface` | Red Hat:enterprise_linux:7::computenode | All versions | 0:4.5.0-23.el7 | Products: Opensuse Leap, Redhat Libvirt. ## How do I fix CVE-2019-3840? Upgrade to a fixed version. ## Is CVE-2019-3840 being exploited? There is no known exploitation of CVE-2019-3840 in the wild and no public exploit code. ## Other vulnerabilities in Opensuse Leap - [CVE-2015-4902](https://insights.sbomify.com/CVE-2015-4902/): Oracle Java SE Integrity Check (medium 5.3, exploited in the wild) - [CVE-2017-14804](https://insights.sbomify.com/CVE-2017-14804/): package builds could use directory traversal to write outside of target area (critical 9.9) - [CVE-2019-20787](https://insights.sbomify.com/CVE-2019-20787/): Teeworlds before 0.7.4 has an integer overflow when computing a tilemap size. (critical 9.8) - [CVE-2019-8341](https://insights.sbomify.com/CVE-2019-8341/): Code injection in n/a (critical 9.8) - [CVE-2019-6438](https://insights.sbomify.com/CVE-2019-6438/): Other in n/a (critical 9.8) ## Fix prompt for AI coding agents ```text Check this codebase for CVE-2019-3840 and fix it if it is affected. What it is: CVE-2019-3840 is a medium-severity vulnerability in Opensuse Leap, published on 27 Mar 2019. Any signed-in user can exploit it over the network, and only if a user opens a file or follows a link. Exploitation: There is no known exploitation of CVE-2019-3840 in the wild and no public exploit code. Affected product: Opensuse Leap. 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-2019-3840/ (Markdown: https://insights.sbomify.com/CVE-2019-3840/index.md) ``` ## Sources - CVE record: https://www.cve.org/CVERecord?id=CVE-2019-3840 - NVD: https://nvd.nist.gov/vuln/detail/CVE-2019-3840 - OSV: https://osv.dev/vulnerability/CVE-2019-3840 --- From sbomify Insights: https://insights.sbomify.com/CVE-2019-3840/ Summaries are generated and may contain mistakes; the official description above is the record.