# CVE-2023-0464: Excessive Resource Usage Verifying X.509 Policy Constraints > Attackers can cause denial of service via malicious X.509 certificate chains when policy constraints are enabled in OpenSSL. - **Severity:** High 7.5 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/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 Mar 2023 - **Updated:** 14 Oct 2026 - **Also known as:** ALPINE-CVE-2023-0464, AZL-25709, AZL-26731, AZL-31141, AZL-34664, AZL-37680, CLEANSTART-2026-VK59609, CLSA-2026-1777048319, DEBIAN-CVE-2023-0464, GHSA-w2w6-xp88-5cvw, JLSEC-2026-235, OESA-2024-1184, OESA-2024-1185, OESA-2024-1186, OESA-2024-1187, SUSE-SU-2023:1703-1, SUSE-SU-2023:1704-1, SUSE-SU-2023:1737-1, SUSE-SU-2023:1738-1, SUSE-SU-2023:1745-1, SUSE-SU-2023:1746-1, SUSE-SU-2023:1747-1, SUSE-SU-2023:1748-1, SUSE-SU-2023:1754-1, SUSE-SU-2023:1764-1, UBUNTU-CVE-2023-0464, openSUSE-SU-2024:12824-1, openSUSE-SU-2024:12825-1, openSUSE-SU-2026:10199-1 ## What is CVE-2023-0464? CVE-2023-0464 is a high-severity denial of service vulnerability in Openssl Openssl, published on 22 Mar 2023. An attacker can exploit it over the internet without logging in, with no action from the victim. ### Official description A security vulnerability has been identified in all supported versions of OpenSSL related to the verification of X.509 certificate chains that include policy constraints. Attackers may be able to exploit this vulnerability by creating a malicious certificate chain that triggers exponential use of computational resources, leading to a denial-of-service (DoS) attack on affected systems. Policy processing is disabled by default but can be enabled by passing the `-policy' argument to the command line utilities or by calling the `X509_VERIFY_PARAM_set1_policies()' function. Weakness: CWE-295 (Improper Certificate Validation) ## Which versions are affected by CVE-2023-0464? It affects 1 product. | Package | Ecosystem | Affected | Fixed in | | --- | --- | --- | --- | | `openssl-1_0_0` | SUSE:Enterprise Storage 7 | All versions | 1.0.2p-150000.3.70.1 | | `openssl-1_0_0` | SUSE:Enterprise Storage 7.1 | All versions | 1.0.2p-150000.3.70.1 | | `openssl-1_1` | SUSE:Linux Enterprise High Performance Computing 15 SP1-LTSS | All versions | 1.1.0i-150100.14.45.1 | | `openssl-1_0_0` | SUSE:Linux Enterprise High Performance Computing 15 SP3-ESPOS | All versions | 1.0.2p-150000.3.70.1 | | `openssl-1_0_0` | SUSE:Linux Enterprise High Performance Computing 15 SP3-LTSS | All versions | 1.0.2p-150000.3.70.1 | | `openssl-1_1` | SUSE:Linux Enterprise Micro 5.3 | All versions | 1.1.1l-150400.7.31.2 | | `openssl-1_1` | SUSE:Linux Enterprise Micro 5.4 | All versions | 1.1.1l-150400.7.31.2 | | `openssl-1_1` | SUSE:Linux Enterprise Module for Basesystem 15 SP4 | All versions | 1.1.1l-150400.7.31.2 | | `openssl-3` | SUSE:Linux Enterprise Module for Basesystem 15 SP4 | All versions | 3.0.1-150400.4.20.1 | | `compat-openssl098` | SUSE:Linux Enterprise Module for Legacy 12 | All versions | 0.9.8j-106.45.1 | | `openssl-1_0_0` | SUSE:Linux Enterprise Module for Legacy 15 SP4 | All versions | 1.0.2p-150000.3.70.1 | | `openssl` | SUSE:Linux Enterprise Server 11 SP4 LTSS EXTREME CORE | All versions | 0.9.8j-0.106.63.1 | | `openssl1` | SUSE:Linux Enterprise Server 11 SP4 LTSS EXTREME CORE | All versions | 1.0.1g-0.58.59.1 | | `openssl` | SUSE:Linux Enterprise Server 12 SP2-BCL | All versions | 1.0.2j-60.89.1 | | `openssl-1_0_0` | SUSE:Linux Enterprise Server 12 SP4-ESPOS | All versions | 1.0.2p-3.69.1 | | `openssl-1_1` | SUSE:Linux Enterprise Server 12 SP4-ESPOS | All versions | 1.1.1d-2.78.1 | | `openssl-1_0_0` | SUSE:Linux Enterprise Server 12 SP4-LTSS | All versions | 1.0.2p-3.69.1 | | `openssl-1_1` | SUSE:Linux Enterprise Server 12 SP4-LTSS | All versions | 1.1.1d-2.78.1 | | `openssl-1_0_0` | SUSE:Linux Enterprise Server 12 SP5 | All versions | 1.0.2p-3.69.1 | | `openssl-1_1` | SUSE:Linux Enterprise Server 12 SP5 | All versions | 1.1.1d-2.78.1 | | `openssl-1_0_0` | SUSE:Linux Enterprise Server 15 SP1-LTSS | All versions | 1.0.2p-150000.3.70.1 | | `openssl-1_1` | SUSE:Linux Enterprise Server 15 SP1-LTSS | All versions | 1.1.0i-150100.14.45.1 | | `openssl-1_0_0` | SUSE:Linux Enterprise Server 15 SP2-LTSS | All versions | 1.0.2p-150000.3.70.1 | | `openssl-1_0_0` | SUSE:Linux Enterprise Server 15 SP3-LTSS | All versions | 1.0.2p-150000.3.70.1 | | `compat-openssl098` | SUSE:Linux Enterprise Server for SAP Applications 12 SP4 | All versions | 0.9.8j-106.45.1 | | `openssl-1_0_0` | SUSE:Linux Enterprise Server for SAP Applications 12 SP4 | All versions | 1.0.2p-3.69.1 | | `openssl-1_1` | SUSE:Linux Enterprise Server for SAP Applications 12 SP4 | All versions | 1.1.1d-2.78.1 | | `compat-openssl098` | SUSE:Linux Enterprise Server for SAP Applications 12 SP5 | All versions | 0.9.8j-106.45.1 | | `openssl-1_0_0` | SUSE:Linux Enterprise Server for SAP Applications 12 SP5 | All versions | 1.0.2p-3.69.1 | | `openssl-1_1` | SUSE:Linux Enterprise Server for SAP Applications 12 SP5 | All versions | 1.1.1d-2.78.1 | | `openssl-1_0_0` | SUSE:Linux Enterprise Server for SAP Applications 15 SP1 | All versions | 1.0.2p-150000.3.70.1 | | `openssl-1_1` | SUSE:Linux Enterprise Server for SAP Applications 15 SP1 | All versions | 1.1.0i-150100.14.45.1 | | `openssl-1_0_0` | SUSE:Linux Enterprise Server for SAP Applications 15 SP2 | All versions | 1.0.2p-150000.3.70.1 | | `openssl-1_0_0` | SUSE:Linux Enterprise Server for SAP Applications 15 SP3 | All versions | 1.0.2p-150000.3.70.1 | | `openssl-1_0_0` | SUSE:Linux Enterprise Software Development Kit 12 SP5 | All versions | 1.0.2p-3.69.1 | | `openssl-1_1` | SUSE:Linux Enterprise Software Development Kit 12 SP5 | All versions | 1.1.1d-2.78.1 | | `openssl-1_0_0` | SUSE:OpenStack Cloud 9 | All versions | 1.0.2p-3.69.1 | | `openssl-1_1` | SUSE:OpenStack Cloud 9 | All versions | 1.1.1d-2.78.1 | | `openssl-1_0_0` | SUSE:OpenStack Cloud Crowbar 9 | All versions | 1.0.2p-3.69.1 | | `openssl-1_1` | SUSE:OpenStack Cloud Crowbar 9 | All versions | 1.1.1d-2.78.1 | Products: Openssl Openssl. ## How do I fix CVE-2023-0464? Apply the vendor's patch. ## Is CVE-2023-0464 being exploited? There is no known exploitation of CVE-2023-0464 in the wild and no public exploit code. Public exploit code: - https://github.com/Trinadh465/Openssl_1.1.1g_CVE-2023-0464 (github_poc): https://github.com/Trinadh465/Openssl_1.1.1g_CVE-2023-0464 ## Other vulnerabilities in Openssl Openssl - [CVE-2009-3245](https://insights.sbomify.com/CVE-2009-3245/): Null dereference in n/a (critical 10.0) - [CVE-2006-3738](https://insights.sbomify.com/CVE-2006-3738/): Memory corruption in n/a (critical 10.0) - [CVE-2026-63073](https://insights.sbomify.com/CVE-2026-63073/): Untrusted Sender DN Used as Format String in CMP Response Validation (critical 9.8) - [CVE-2016-6309](https://insights.sbomify.com/CVE-2016-6309/): Use after free in n/a (critical 9.8) - [CVE-2016-0799](https://insights.sbomify.com/CVE-2016-0799/): Integer overflow in n/a (critical 9.8) ## Fix prompt for AI coding agents ```text Check this codebase for CVE-2023-0464 and fix it if it is affected. What it is: CVE-2023-0464 is a high-severity denial of service vulnerability in Openssl Openssl, published on 22 Mar 2023. 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-2023-0464 in the wild and no public exploit code. Affected product: Openssl Openssl. 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-2023-0464/ (Markdown: https://insights.sbomify.com/CVE-2023-0464/index.md) ``` ## Sources - CVE record: https://www.cve.org/CVERecord?id=CVE-2023-0464 - NVD: https://nvd.nist.gov/vuln/detail/CVE-2023-0464 - OSV: https://osv.dev/vulnerability/CVE-2023-0464 --- From sbomify Insights: https://insights.sbomify.com/CVE-2023-0464/ Summaries are generated and may contain mistakes; the official description above is the record.