# CVE-2024-2511: Unbounded memory growth with session handling in TLSv1.3 > Attackers can cause unbounded memory growth and denial of service in TLSv1.3 servers using non-default SSL_OP_NO_TICKET configuration. - **Severity:** Medium 5.9 (`CVSS:3.1/AV:N/AC:H/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:** 8 Apr 2024 - **Updated:** 15 Oct 2026 - **Also known as:** ALPINE-CVE-2024-2511, AZL-39794, AZL-39797, AZL-40192, AZL-42700, AZL-42765, AZL-42949, AZL-47649, AZL-78543, BELL-CVE-2024-2511, CLEANSTART-2026-MP77998, CLSA-2024-1735311149, CLSA-2026-1780513164, DEBIAN-CVE-2024-2511, GHSA-299c-jvhc-gxj8, JLSEC-2026-249, MGASA-2024-0129, OESA-2024-1513, OESA-2024-1531, SUSE-SU-2024:1633-1, SUSE-SU-2024:1634-1, SUSE-SU-2024:1808-1, SUSE-SU-2024:1949-1, UBUNTU-CVE-2024-2511, openSUSE-SU-2024:13937-1, openSUSE-SU-2024:13942-1 ## What is CVE-2024-2511? CVE-2024-2511 is a medium-severity denial of service vulnerability in OpenSSL, published on 8 Apr 2024. An attacker can exploit it over the internet without logging in, with no action from the victim. ### Official description Issue summary: Some non-default TLS server configurations can cause unbounded memory growth when processing TLSv1.3 sessions Impact summary: An attacker may exploit certain server configurations to trigger unbounded memory growth that would lead to a Denial of Service This problem can occur in TLSv1.3 if the non-default SSL_OP_NO_TICKET option is being used (but not if early_data support is also configured and the default anti-replay protection is in use). In this case, under certain conditions, the session cache can get into an incorrect state and it will fail to flush properly as it fills. The session cache will continue to grow in an unbounded manner. A malicious client could deliberately create the scenario for this failure to force a Denial of Service. It may also happen by accident in normal operation. This issue only affects TLS servers supporting TLSv1.3. It does not affect TLS clients. The FIPS modules in 3.2, 3.1 and 3.0 are not affected by this issue. OpenSSL 1.0.2 is also not affected by this issue. Weakness: CWE-1325 (Improperly Controlled Sequential Memory Allocation) ## Which versions are affected by CVE-2024-2511? | Package | Ecosystem | Affected | Fixed in | | --- | --- | --- | --- | | `openssl-1_1` | SUSE:Enterprise Storage 7.1 | All versions | 1.1.1d-150200.11.88.1 | | `openssl-1_1` | SUSE:Linux Enterprise High Performance Computing 15 SP2-LTSS | All versions | 1.1.1d-150200.11.88.1 | | `openssl-1_1` | SUSE:Linux Enterprise High Performance Computing 15 SP3-LTSS | All versions | 1.1.1d-150200.11.88.1 | | `openssl-1_1` | SUSE:Linux Enterprise High Performance Computing 15 SP4-ESPOS | All versions | 1.1.1l-150400.7.66.2 | | `openssl-1_1` | SUSE:Linux Enterprise High Performance Computing 15 SP4-LTSS | All versions | 1.1.1l-150400.7.66.2 | | `openssl-1_1` | SUSE:Linux Enterprise Micro 5.1 | All versions | 1.1.1d-150200.11.88.1 | | `openssl-1_1` | SUSE:Linux Enterprise Micro 5.2 | All versions | 1.1.1d-150200.11.88.1 | | `openssl-1_1` | SUSE:Linux Enterprise Micro 5.3 | All versions | 1.1.1l-150400.7.66.2 | | `openssl-1_1` | SUSE:Linux Enterprise Micro 5.4 | All versions | 1.1.1l-150400.7.66.2 | | `openssl-1_1` | SUSE:Linux Enterprise Micro 5.5 | All versions | 1.1.1l-150500.17.28.2 | | `openssl-1_1` | SUSE:Linux Enterprise Module for Basesystem 15 SP5 | All versions | 1.1.1l-150500.17.28.2 | | `openssl-3` | SUSE:Linux Enterprise Module for Basesystem 15 SP5 | All versions | 3.0.8-150500.5.30.1 | | `openssl-1_1` | SUSE:Linux Enterprise Server 15 SP2-LTSS | All versions | 1.1.1d-150200.11.88.1 | | `openssl-1_1` | SUSE:Linux Enterprise Server 15 SP3-LTSS | All versions | 1.1.1d-150200.11.88.1 | | `openssl-1_1` | SUSE:Linux Enterprise Server 15 SP4-LTSS | All versions | 1.1.1l-150400.7.66.2 | | `openssl-1_1` | SUSE:Linux Enterprise Server for SAP Applications 15 SP2 | All versions | 1.1.1d-150200.11.88.1 | | `openssl-1_1` | SUSE:Linux Enterprise Server for SAP Applications 15 SP3 | All versions | 1.1.1d-150200.11.88.1 | | `openssl-1_1` | SUSE:Linux Enterprise Server for SAP Applications 15 SP4 | All versions | 1.1.1l-150400.7.66.2 | | `openssl-1_1` | SUSE:Manager Proxy 4.3 | All versions | 1.1.1l-150400.7.66.2 | | `openssl-1_1` | SUSE:Manager Server 4.3 | All versions | 1.1.1l-150400.7.66.2 | | `openssl-1_1` | openSUSE:Leap 15.5 | All versions | 1.1.1l-150500.17.28.2 | | `openssl-3` | openSUSE:Leap 15.5 | All versions | 3.0.8-150500.5.30.1 | | `openssl-1_1` | openSUSE:Leap Micro 5.3 | All versions | 1.1.1l-150400.7.66.2 | | `openssl-1_1` | openSUSE:Leap Micro 5.4 | All versions | 1.1.1l-150400.7.66.2 | | `openssl-1_1` | openSUSE:Tumbleweed | All versions | 1.1.1w-9.1 | | `openssl-3` | openSUSE:Tumbleweed | All versions | 3.1.4-6.1 | ## How do I fix CVE-2024-2511? Apply the vendor's patch. ## Is CVE-2024-2511 being exploited? There is no known exploitation of CVE-2024-2511 in the wild and no public exploit code. ## Fix prompt for AI coding agents ```text Check this codebase for CVE-2024-2511 and fix it if it is affected. What it is: CVE-2024-2511 is a medium-severity denial of service vulnerability in OpenSSL, published on 8 Apr 2024. 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-2024-2511 in the wild and no public exploit code. Affected product: 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-2024-2511/ (Markdown: https://insights.sbomify.com/CVE-2024-2511/index.md) ``` ## Sources - CVE record: https://www.cve.org/CVERecord?id=CVE-2024-2511 - NVD: https://nvd.nist.gov/vuln/detail/CVE-2024-2511 - OSV: https://osv.dev/vulnerability/CVE-2024-2511 --- From sbomify Insights: https://insights.sbomify.com/CVE-2024-2511/ Summaries are generated and may contain mistakes; the official description above is the record.