# CVE-2021-20319: coreos-installer improperly verifies GPG signature when decompressing gzipped artifact > Attackers can bypass signature verification in coreos-installer to install unsigned content, gaining full access to the node. - **Severity:** High 7.8 (`CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/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:** 4 Mar 2022 - **Updated:** 3 Aug 2024 - **Also known as:** GHSA-3r3g-g73x-g593, RHSA-2021:3926, RHSA-2021:3930, RHSA-2021:3934, RHSA-2021:4008, RUSTSEC-2022-0103 ## What is CVE-2021-20319? CVE-2021-20319 is a high-severity vulnerability in coreos-installer, published on 4 Mar 2022. 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 An improper signature verification vulnerability was found in coreos-installer. A specially crafted gzip installation image can bypass the image signature verification and as a consequence can lead to the installation of unsigned content. An attacker able to modify the original installation image can write arbitrary data, and achieve full access to the node being installed. Weakness: CWE-347 (Improper Verification of Cryptographic Signature) ## Which versions are affected by CVE-2021-20319? 3 open source packages ship an affected version, including coreos-installer. It affects 1 product. | Package | Ecosystem | Affected | Fixed in | | --- | --- | --- | --- | | `coreos-installer` | crates.io | All versions | 0.10.1 | | `coreos-installer` | crates.io | All versions | 0.10.1 | | `coreos-installer` | crates.io | From 0.0.0-0 | 0.10.1 | | `coreos-installer` | Red Hat:openshift:4.6::el8 | All versions | 0:0.6.0-4.rhaos4.6.el8 | | `coreos-installer-bootinfra` | Red Hat:openshift:4.6::el8 | All versions | 0:0.6.0-4.rhaos4.6.el8 | | `coreos-installer-bootinfra-debuginfo` | Red Hat:openshift:4.6::el8 | All versions | 0:0.6.0-4.rhaos4.6.el8 | | `coreos-installer-debuginfo` | Red Hat:openshift:4.6::el8 | All versions | 0:0.6.0-4.rhaos4.6.el8 | | `coreos-installer-debugsource` | Red Hat:openshift:4.6::el8 | All versions | 0:0.6.0-4.rhaos4.6.el8 | | `coreos-installer` | Red Hat:openshift:4.7::el8 | All versions | 0:0.8.0-4.rhaos4.7.el8 | | `coreos-installer-bootinfra` | Red Hat:openshift:4.7::el8 | All versions | 0:0.8.0-4.rhaos4.7.el8 | | `coreos-installer-bootinfra-debuginfo` | Red Hat:openshift:4.7::el8 | All versions | 0:0.8.0-4.rhaos4.7.el8 | | `coreos-installer-debuginfo` | Red Hat:openshift:4.7::el8 | All versions | 0:0.8.0-4.rhaos4.7.el8 | | `coreos-installer-debugsource` | Red Hat:openshift:4.7::el8 | All versions | 0:0.8.0-4.rhaos4.7.el8 | | `coreos-installer` | Red Hat:openshift:4.8::el8 | All versions | 0:0.9.0-7.rhaos4.8.el8 | | `coreos-installer-bootinfra` | Red Hat:openshift:4.8::el8 | All versions | 0:0.9.0-7.rhaos4.8.el8 | | `coreos-installer-bootinfra-debuginfo` | Red Hat:openshift:4.8::el8 | All versions | 0:0.9.0-7.rhaos4.8.el8 | | `coreos-installer-debuginfo` | Red Hat:openshift:4.8::el8 | All versions | 0:0.9.0-7.rhaos4.8.el8 | | `coreos-installer-debugsource` | Red Hat:openshift:4.8::el8 | All versions | 0:0.9.0-7.rhaos4.8.el8 | | `coreos-installer` | Red Hat:openshift:4.9::el8 | All versions | 0:0.10.1-1.rhaos4.9.el8 | | `coreos-installer-bootinfra` | Red Hat:openshift:4.9::el8 | All versions | 0:0.10.1-1.rhaos4.9.el8 | | `coreos-installer-bootinfra-debuginfo` | Red Hat:openshift:4.9::el8 | All versions | 0:0.10.1-1.rhaos4.9.el8 | | `coreos-installer-debuginfo` | Red Hat:openshift:4.9::el8 | All versions | 0:0.10.1-1.rhaos4.9.el8 | | `coreos-installer-debugsource` | Red Hat:openshift:4.9::el8 | All versions | 0:0.10.1-1.rhaos4.9.el8 | Products: Redhat Coreos-Installer. ## How do I fix CVE-2021-20319? Upgrade coreos-installer to 0.10.1 or later. ## Is CVE-2021-20319 being exploited? There is no known exploitation of CVE-2021-20319 in the wild and no public exploit code. ## Other vulnerabilities in coreos-installer - [CVE-2021-3917](https://insights.sbomify.com/CVE-2021-3917/): coreos-installer < 0.10.0 writes world-readable Ignition config to installed system (medium 5.5) ## Fix prompt for AI coding agents ```text Check this codebase for CVE-2021-20319 and fix it if it is affected. What it is: CVE-2021-20319 is a high-severity vulnerability in coreos-installer, published on 4 Mar 2022. 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-2021-20319 in the wild and no public exploit code. Affected packages and fixed versions: - coreos-installer (crates.io): affected all versions; fixed in 0.10.1 - coreos-installer (crates.io): affected all versions; fixed in 0.10.1 - coreos-installer (crates.io): affected from 0.0.0-0; fixed in 0.10.1 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-2021-20319/ (Markdown: https://insights.sbomify.com/CVE-2021-20319/index.md) ``` ## Sources - CVE record: https://www.cve.org/CVERecord?id=CVE-2021-20319 - NVD: https://nvd.nist.gov/vuln/detail/CVE-2021-20319 - OSV: https://osv.dev/vulnerability/CVE-2021-20319 --- From sbomify Insights: https://insights.sbomify.com/CVE-2021-20319/ Summaries are generated and may contain mistakes; the official description above is the record.