# CVE-2020-24659: An issue was discovered in GnuTLS before 3.6.15. - **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 - **Fix available:** Yes - **Published:** 4 Sep 2020 - **Updated:** 14 Oct 2026 - **Also known as:** ALPINE-CVE-2020-24659, AZL-6445, DEBIAN-CVE-2020-24659, GHSA-wx7m-j6j8-xm63, JLSEC-2026-519, MGASA-2020-0379, OESA-2021-1046, RHSA-2020:5483, SUSE-SU-2020:2864-1, SUSE-SU-2020:2864-2, SUSE-SU-2020:2988-1, UBUNTU-CVE-2020-24659, USN-4491-1, openSUSE-SU-2020:1724-1, openSUSE-SU-2020:1743-1 ## What is CVE-2020-24659? CVE-2020-24659 is a high-severity vulnerability in Canonical Ubuntu Linux, published on 4 Sep 2020. ### Official description An issue was discovered in GnuTLS before 3.6.15. A server can trigger a NULL pointer dereference in a TLS 1.3 client if a no_renegotiation alert is sent with unexpected timing, and then an invalid second handshake occurs. The crash happens in the application's error handling path, where the gnutls_deinit function is called after detecting a handshake failure. Weakness: CWE-787 (Out-of-bounds Write), CWE-476 (NULL Pointer Dereference) ## Which versions are affected by CVE-2020-24659? It affects 4 products. | Package | Ecosystem | Affected | Fixed in | | --- | --- | --- | --- | | `gnutls-c++` | Red Hat:enterprise_linux:8::appstream | All versions | 0:3.6.14-7.el8_3 | | `gnutls-c++-debuginfo` | Red Hat:enterprise_linux:8::appstream | All versions | 0:3.6.14-7.el8_3 | | `gnutls-dane` | Red Hat:enterprise_linux:8::appstream | All versions | 0:3.6.14-7.el8_3 | | `gnutls-dane-debuginfo` | Red Hat:enterprise_linux:8::appstream | All versions | 0:3.6.14-7.el8_3 | | `gnutls-debuginfo` | Red Hat:enterprise_linux:8::appstream | All versions | 0:3.6.14-7.el8_3 | | `gnutls-debugsource` | Red Hat:enterprise_linux:8::appstream | All versions | 0:3.6.14-7.el8_3 | | `gnutls-devel` | Red Hat:enterprise_linux:8::appstream | All versions | 0:3.6.14-7.el8_3 | | `gnutls-utils` | Red Hat:enterprise_linux:8::appstream | All versions | 0:3.6.14-7.el8_3 | | `gnutls-utils-debuginfo` | Red Hat:enterprise_linux:8::appstream | All versions | 0:3.6.14-7.el8_3 | | `gnutls` | Red Hat:enterprise_linux:8::baseos | All versions | 0:3.6.14-7.el8_3 | | `gnutls-c++-debuginfo` | Red Hat:enterprise_linux:8::baseos | All versions | 0:3.6.14-7.el8_3 | | `gnutls-dane-debuginfo` | Red Hat:enterprise_linux:8::baseos | All versions | 0:3.6.14-7.el8_3 | | `gnutls-debuginfo` | Red Hat:enterprise_linux:8::baseos | All versions | 0:3.6.14-7.el8_3 | | `gnutls-debugsource` | Red Hat:enterprise_linux:8::baseos | All versions | 0:3.6.14-7.el8_3 | | `gnutls-utils-debuginfo` | Red Hat:enterprise_linux:8::baseos | All versions | 0:3.6.14-7.el8_3 | | `gnutls` | SUSE:Linux Enterprise High Performance Computing 15-ESPOS | All versions | 3.6.7-6.34.1 | | `gnutls` | SUSE:Linux Enterprise High Performance Computing 15-LTSS | All versions | 3.6.7-6.34.1 | | `gnutls` | SUSE:Linux Enterprise Module for Basesystem 15 SP1 | All versions | 3.6.7-6.34.1 | | `gnutls` | SUSE:Linux Enterprise Module for Basesystem 15 SP2 | All versions | 3.6.7-14.4.1 | | `gnutls` | SUSE:Linux Enterprise Module for Certifications 15 SP3 | All versions | 3.6.7-14.4.1 | | `gnutls` | SUSE:Linux Enterprise Server 15-LTSS | All versions | 3.6.7-6.34.1 | | `gnutls` | SUSE:Linux Enterprise Server for SAP Applications 15 | All versions | 3.6.7-6.34.1 | | `gnutls` | openSUSE:Leap 15.1 | All versions | 3.6.7-lp151.2.21.1 | | `gnutls` | openSUSE:Leap 15.2 | All versions | 3.6.7-lp152.9.3.2 | Products: Canonical Ubuntu Linux, Fedoraproject Fedora, Gnu Gnutls, Opensuse Leap. ## How do I fix CVE-2020-24659? Upgrade to a fixed version. ## Is CVE-2020-24659 being exploited? There is no known exploitation of CVE-2020-24659 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-2020-24659 and fix it if it is affected. What it is: CVE-2020-24659 is a high-severity vulnerability in Canonical Ubuntu Linux, published on 4 Sep 2020. Exploitation: There is no known exploitation of CVE-2020-24659 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-2020-24659/ (Markdown: https://insights.sbomify.com/CVE-2020-24659/index.md) ``` ## Sources - CVE record: https://www.cve.org/CVERecord?id=CVE-2020-24659 - NVD: https://nvd.nist.gov/vuln/detail/CVE-2020-24659 - OSV: https://osv.dev/vulnerability/CVE-2020-24659 --- From sbomify Insights: https://insights.sbomify.com/CVE-2020-24659/ Summaries are generated and may contain mistakes; the official description above is the record.