# CVE-2026-44236: rabbitmq-c: Heap buffer overflow in AMQP login handshake via undersized connection.tune.frame_max > A malicious AMQP server can trigger a heap buffer overflow in the rabbitmq-c client library during login, causing denial of service or potential code execution. - **Severity:** High 7.1 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:H`) - **Exploited in the wild:** Not known - **Login needed:** Not needed - **Attackable:** Over the internet - **Victim action needed:** A user has to click or open something - **Fix available:** Yes - **Published:** 17 Sep 2026 - **Updated:** 21 Sep 2026 - **Also known as:** ALSA-2026:75582, ALSA-2026:82094, ALSA-2026:84795, AZL-105087, BIT-rabbitmq-c-2026-44236, CLSA-2026-1792594240, CLSA-2026-1792765036, DEBIAN-CVE-2026-44236, ECHO-6381-0eb9-8dbd, GHSA-jh48-qjf5-fx5v, RHSA-2026:75582, RHSA-2026:82094, RHSA-2026:84795, RLSA-2026:75582, RLSA-2026:82094, RLSA-2026:84795, UBUNTU-CVE-2026-44236 ## What is CVE-2026-44236? CVE-2026-44236 is a high-severity memory corruption vulnerability in alanxz rabbitmq-c, published on 17 Sep 2026. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link. ### Official description rabbitmq-c is a C-language AMQP client library for RabbitMQ. Prior to 0.16.0, a malicious AMQP server can send an undersized connection.tune.frame_max value during amqp_login(), and rabbitmq-c accepts the value in amqp_login_inner() in librabbitmq/amqp_socket.c. amqp_tune_connection() in librabbitmq/amqp_connection.c uses frame_max to reallocate the outbound buffer without enforcing AMQP_FRAME_MIN_SIZE. Immediate serialization of connection.tune-ok through amqp_frame_to_bytes() writes beyond the undersized heap allocation, causing memory corruption and likely denial of service. An on-path attacker can also trigger the flaw against plaintext AMQP traffic. Code execution is theoretically possible but was not demonstrated. This issue is fixed in version 0.16.0. Weakness: CWE-122 (Heap-based Buffer Overflow) ## Which versions are affected by CVE-2026-44236? 1 open source package ship an affected version, including rabbitmq-c. | Package | Ecosystem | Affected | Fixed in | | --- | --- | --- | --- | | `rabbitmq-c` | Bitnami | All versions | 0.16.0 | | `librabbitmq` | AlmaLinux:10 | All versions | 0.14.0-3.el10_2.1 | | `librabbitmq-devel` | AlmaLinux:10 | All versions | 0.14.0-3.el10_2.1 | | `librabbitmq-tools` | AlmaLinux:10 | All versions | 0.14.0-3.el10_2.1 | | `librabbitmq-devel` | AlmaLinux:8 | All versions | 0.9.0-6.el8_10 | | `librabbitmq` | AlmaLinux:9 | All versions | 0.11.0-7.el9_8.1 | | `librabbitmq-devel` | AlmaLinux:9 | All versions | 0.11.0-7.el9_8.1 | | `librabbitmq-tools` | AlmaLinux:9 | All versions | 0.11.0-7.el9_8.1 | | `librabbitmq` | Red Hat:enterprise_linux:10.2 | All versions | 0:0.14.0-3.el10_2.1 | | `librabbitmq-debuginfo` | Red Hat:enterprise_linux:10.2 | All versions | 0:0.14.0-3.el10_2.1 | | `librabbitmq-debugsource` | Red Hat:enterprise_linux:10.2 | All versions | 0:0.14.0-3.el10_2.1 | | `librabbitmq-devel` | Red Hat:enterprise_linux:10.2 | All versions | 0:0.14.0-3.el10_2.1 | | `librabbitmq-tools` | Red Hat:enterprise_linux:10.2 | All versions | 0:0.14.0-3.el10_2.1 | | `librabbitmq-tools-debuginfo` | Red Hat:enterprise_linux:10.2 | All versions | 0:0.14.0-3.el10_2.1 | | `librabbitmq-debuginfo` | Red Hat:enterprise_linux:8::appstream | All versions | 0:0.9.0-6.el8_10 | | `librabbitmq-debugsource` | Red Hat:enterprise_linux:8::appstream | All versions | 0:0.9.0-6.el8_10 | | `librabbitmq-tools` | Red Hat:enterprise_linux:8::appstream | All versions | 0:0.9.0-6.el8_10 | | `librabbitmq-tools-debuginfo` | Red Hat:enterprise_linux:8::appstream | All versions | 0:0.9.0-6.el8_10 | | `librabbitmq` | Red Hat:enterprise_linux:8::baseos | All versions | 0:0.9.0-6.el8_10 | | `librabbitmq-debuginfo` | Red Hat:enterprise_linux:8::baseos | All versions | 0:0.9.0-6.el8_10 | | `librabbitmq-debugsource` | Red Hat:enterprise_linux:8::baseos | All versions | 0:0.9.0-6.el8_10 | | `librabbitmq-tools-debuginfo` | Red Hat:enterprise_linux:8::baseos | All versions | 0:0.9.0-6.el8_10 | | `librabbitmq-debuginfo` | Red Hat:enterprise_linux:8::crb | All versions | 0:0.9.0-6.el8_10 | | `librabbitmq-debugsource` | Red Hat:enterprise_linux:8::crb | All versions | 0:0.9.0-6.el8_10 | | `librabbitmq-devel` | Red Hat:enterprise_linux:8::crb | All versions | 0:0.9.0-6.el8_10 | | `librabbitmq-tools-debuginfo` | Red Hat:enterprise_linux:8::crb | All versions | 0:0.9.0-6.el8_10 | | `librabbitmq` | Red Hat:enterprise_linux:9::appstream | All versions | 0:0.11.0-7.el9_8.1 | | `librabbitmq-debuginfo` | Red Hat:enterprise_linux:9::appstream | All versions | 0:0.11.0-7.el9_8.1 | | `librabbitmq-debugsource` | Red Hat:enterprise_linux:9::appstream | All versions | 0:0.11.0-7.el9_8.1 | | `librabbitmq-tools` | Red Hat:enterprise_linux:9::appstream | All versions | 0:0.11.0-7.el9_8.1 | | `librabbitmq-tools-debuginfo` | Red Hat:enterprise_linux:9::appstream | All versions | 0:0.11.0-7.el9_8.1 | | `librabbitmq-debuginfo` | Red Hat:enterprise_linux:9::crb | All versions | 0:0.11.0-7.el9_8.1 | | `librabbitmq-debugsource` | Red Hat:enterprise_linux:9::crb | All versions | 0:0.11.0-7.el9_8.1 | | `librabbitmq-devel` | Red Hat:enterprise_linux:9::crb | All versions | 0:0.11.0-7.el9_8.1 | | `librabbitmq-tools-debuginfo` | Red Hat:enterprise_linux:9::crb | All versions | 0:0.11.0-7.el9_8.1 | | `librabbitmq` | Rocky Linux:10 | All versions | 0:0.14.0-3.el10_2.1 | | `librabbitmq` | Rocky Linux:8 | All versions | 0:0.9.0-6.el8_10 | | `librabbitmq` | Rocky Linux:9 | All versions | 0:0.11.0-7.el9_8.1 | ## How do I fix CVE-2026-44236? Upgrade rabbitmq-c to 0.16.0 or later. ## Is CVE-2026-44236 being exploited? It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-44236 exists. ## Fix prompt for AI coding agents ```text Check this codebase for CVE-2026-44236 and fix it if it is affected. What it is: CVE-2026-44236 is a high-severity memory corruption vulnerability in alanxz rabbitmq-c, published on 17 Sep 2026. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link. Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-44236 exists. Affected packages and fixed versions: - rabbitmq-c (Bitnami): affected all versions; fixed in 0.16.0 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-2026-44236/ (Markdown: https://insights.sbomify.com/CVE-2026-44236/index.md) ``` ## Sources - CVE record: https://www.cve.org/CVERecord?id=CVE-2026-44236 - NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-44236 - OSV: https://osv.dev/vulnerability/CVE-2026-44236 --- From sbomify Insights: https://insights.sbomify.com/CVE-2026-44236/ Summaries are generated and may contain mistakes; the official description above is the record.