# CVE-2026-94184: Fetchmail: fetchmail: stack-based buffer overflow in ntlm authentication (fetchmail-sa-2026-01) > A stack-based buffer overflow in fetchmail's NTLM authentication allows remote code execution or denial of service via a malicious mail server. - **Severity:** Medium 5.3 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L`) - **Exploited in the wild:** Not known - **Login needed:** Not needed - **Attackable:** Over the internet - **Victim action needed:** Not needed - **Fix available:** Yes - **Published:** 21 Sep 2026 - **Updated:** 21 Oct 2026 - **Also known as:** ALSA-2026:85959, ALSA-2026:86981, ALSA-2026:86982, AZL-105066, DEBIAN-CVE-2026-94184, GHSA-5pfw-5pv2-2pc6, OESA-2026-4206, OESA-2026-4207, OESA-2026-4208, OESA-2026-4209, RLSA-2026:85959, RLSA-2026:86981, RLSA-2026:86982, SUSE-SU-2026:24221-1, SUSE-SU-2026:4567-1, SUSE-SU-2026:4604-1, SUSE-SU-2026:4605-1, UBUNTU-CVE-2026-94184, openSUSE-SU-2026:12115-1, openSUSE-SU-2026:22077-1 ## What is CVE-2026-94184? CVE-2026-94184 is a medium-severity memory corruption vulnerability in Red Hat Enterprise Linux 10, published on 21 Sep 2026. An attacker can exploit it over the internet without logging in, with no action from the victim. ### Official description A stack-based buffer overflow flaw was found in fetchmail when built with NTLM support. A malicious or compromised mail server advertising NTLM authentication can send a crafted Type 2 challenge that causes fetchmail to write past a fixed stack buffer while building the NTLM authenticate response. This may lead to remote code execution depending on stack-frame layout, or to authentication failure or process termination under memory hardening. Weakness: CWE-121 (Stack-based Buffer Overflow) ## Which versions are affected by CVE-2026-94184? | Package | Ecosystem | Affected | Fixed in | | --- | --- | --- | --- | | `fetchmail` | AlmaLinux:10 | All versions | 6.4.38-3.el10_2.1 | | `fetchmail` | AlmaLinux:8 | All versions | 6.4.24-1.el8_10.1 | | `fetchmail` | AlmaLinux:9 | All versions | 6.4.24-1.el9_8.1 | | `fetchmail` | Rocky Linux:10 | All versions | 0:6.4.38-3.el10_2.1 | | `fetchmail` | Rocky Linux:8 | All versions | 0:6.4.24-1.el8_10.1 | | `fetchmail` | Rocky Linux:9 | All versions | 0:6.4.24-1.el9_8.1 | | `fetchmail` | SUSE:Linux Enterprise High Performance Computing 15 SP4-ESPOS | All versions | 6.4.22-150000.20.32.1 | | `fetchmail` | SUSE:Linux Enterprise High Performance Computing 15 SP4-LTSS | All versions | 6.4.22-150000.20.32.1 | | `fetchmail` | SUSE:Linux Enterprise High Performance Computing 15 SP5-ESPOS | All versions | 6.4.22-150000.20.32.1 | | `fetchmail` | SUSE:Linux Enterprise High Performance Computing 15 SP5-LTSS | All versions | 6.4.22-150000.20.32.1 | | `fetchmail` | SUSE:Linux Enterprise Module for Basesystem 15 SP7 | All versions | 6.4.22-150600.35.6.1 | | `fetchmail` | SUSE:Linux Enterprise Module for Desktop Applications 15 SP7 | All versions | 6.4.22-150600.35.6.1 | | `fetchmail` | SUSE:Linux Enterprise Server 12 SP5-LTSS | All versions | 6.3.26-13.24.1 | | `fetchmail` | SUSE:Linux Enterprise Server 15 SP4-LTSS | All versions | 6.4.22-150000.20.32.1 | | `fetchmail` | SUSE:Linux Enterprise Server 15 SP5-LTSS | All versions | 6.4.22-150000.20.32.1 | | `fetchmail` | SUSE:Linux Enterprise Server 15 SP6-LTSS | All versions | 6.4.22-150600.35.6.1 | | `fetchmail` | SUSE:Linux Enterprise Server 16.0 | All versions | 6.5.2-160000.4.1 | | `fetchmail` | SUSE:Linux Enterprise Server LTSS Extended Security 12 SP5 | All versions | 6.3.26-13.24.1 | | `fetchmail` | SUSE:Linux Enterprise Server for SAP Applications 15 SP4 | All versions | 6.4.22-150000.20.32.1 | | `fetchmail` | SUSE:Linux Enterprise Server for SAP Applications 15 SP5 | All versions | 6.4.22-150000.20.32.1 | | `fetchmail` | SUSE:Linux Enterprise Server for SAP Applications 15 SP6 | All versions | 6.4.22-150600.35.6.1 | | `fetchmail` | SUSE:Linux Enterprise Server for SAP applications 16.0 | All versions | 6.5.2-160000.4.1 | | `fetchmail` | openSUSE:Leap 16.0 | All versions | 6.5.2-160000.4.1 | | `fetchmail` | openSUSE:Tumbleweed | All versions | 6.6.8-1.1 | ## How do I fix CVE-2026-94184? Apply the vendor's patch. ## Is CVE-2026-94184 being exploited? There is no known exploitation of CVE-2026-94184 in the wild and no public exploit code. ## Fix prompt for AI coding agents ```text Check this codebase for CVE-2026-94184 and fix it if it is affected. What it is: CVE-2026-94184 is a medium-severity memory corruption vulnerability in Red Hat Enterprise Linux 10, published on 21 Sep 2026. 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-2026-94184 in the wild and no public exploit code. Affected product: Red Hat Enterprise Linux 10. 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-2026-94184/ (Markdown: https://insights.sbomify.com/CVE-2026-94184/index.md) ``` ## Sources - CVE record: https://www.cve.org/CVERecord?id=CVE-2026-94184 - NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-94184 - OSV: https://osv.dev/vulnerability/CVE-2026-94184 --- From sbomify Insights: https://insights.sbomify.com/CVE-2026-94184/ Summaries are generated and may contain mistakes; the official description above is the record.