# CVE-2022-39028: Null dereference in n/a > A NULL pointer dereference in telnetd allows remote attackers to cause a denial of service by crashing the service repeatedly. - **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:** 30 Aug 2022 - **Updated:** 3 Aug 2024 - **Also known as:** DEBIAN-CVE-2022-39028, GHSA-jq82-jqvw-64w3, MGASA-2022-0394, MGASA-2022-0460, OESA-2024-1354, OESA-2024-1359, OESA-2024-1360, OESA-2024-1361, OESA-2024-1362, OESA-2024-1363, SUSE-SU-2022:3471-1, SUSE-SU-2022:3735-1, SUSE-SU-2022:3783-1, UBUNTU-CVE-2022-39028, openSUSE-SU-2024:12436-1 ## What is CVE-2022-39028? CVE-2022-39028 is a high-severity vulnerability in Debian Debian Linux, published on 30 Aug 2022. An attacker can exploit it over the internet without logging in, with no action from the victim. ### Official description telnetd in GNU Inetutils through 2.3, MIT krb5-appl through 1.0.3, and derivative works has a NULL pointer dereference via 0xff 0xf7 or 0xff 0xf8. In a typical installation, the telnetd application would crash but the telnet service would remain available through inetd. However, if the telnetd application has many crashes within a short time interval, the telnet service would become unavailable after inetd logs a "telnet/tcp server failing (looping), service terminated" error. NOTE: MIT krb5-appl is not supported upstream but is shipped by a few Linux distributions. The affected code was removed from the supported MIT Kerberos 5 (aka krb5) product many years ago, at version 1.8. Weakness: CWE-476 (NULL Pointer Dereference) ## Which versions are affected by CVE-2022-39028? It affects 4 products. | Package | Ecosystem | Affected | Fixed in | | --- | --- | --- | --- | | `telnet` | SUSE:Enterprise Storage 6 | All versions | 1.2-150000.3.6.1 | | `telnet` | SUSE:Enterprise Storage 7 | All versions | 1.2-150000.3.6.1 | | `telnet` | SUSE:Linux Enterprise High Performance Computing 15 SP1-ESPOS | All versions | 1.2-150000.3.6.1 | | `telnet` | SUSE:Linux Enterprise High Performance Computing 15 SP1-LTSS | All versions | 1.2-150000.3.6.1 | | `telnet` | SUSE:Linux Enterprise High Performance Computing 15 SP2-ESPOS | All versions | 1.2-150000.3.6.1 | | `telnet` | SUSE:Linux Enterprise High Performance Computing 15 SP2-LTSS | All versions | 1.2-150000.3.6.1 | | `telnet` | SUSE:Linux Enterprise High Performance Computing 15-ESPOS | All versions | 1.2-150000.3.6.1 | | `telnet` | SUSE:Linux Enterprise High Performance Computing 15-LTSS | All versions | 1.2-150000.3.6.1 | | `telnet` | SUSE:Linux Enterprise Module for Basesystem 15 SP3 | All versions | 1.2-150000.3.6.1 | | `telnet` | SUSE:Linux Enterprise Module for Basesystem 15 SP4 | All versions | 1.2-150000.3.6.1 | | `telnet` | SUSE:Linux Enterprise Module for Legacy 15 SP3 | All versions | 1.2-150000.3.6.1 | | `telnet` | SUSE:Linux Enterprise Module for Legacy 15 SP4 | All versions | 1.2-150000.3.6.1 | | `krb5-appl` | SUSE:Linux Enterprise Server 12 SP2-BCL | All versions | 1.0.3-3.9.1 | | `telnet` | SUSE:Linux Enterprise Server 12 SP2-BCL | All versions | 1.2-167.10.1 | | `krb5-appl` | SUSE:Linux Enterprise Server 12 SP3-BCL | All versions | 1.0.3-3.9.1 | | `telnet` | SUSE:Linux Enterprise Server 12 SP3-BCL | All versions | 1.2-167.10.1 | | `krb5-appl` | SUSE:Linux Enterprise Server 12 SP4-LTSS | All versions | 1.0.3-3.9.1 | | `telnet` | SUSE:Linux Enterprise Server 12 SP4-LTSS | All versions | 1.2-167.10.1 | | `krb5-appl` | SUSE:Linux Enterprise Server 12 SP5 | All versions | 1.0.3-3.9.1 | | `telnet` | SUSE:Linux Enterprise Server 12 SP5 | All versions | 1.2-167.10.1 | | `telnet` | SUSE:Linux Enterprise Server 15 SP1-BCL | All versions | 1.2-150000.3.6.1 | | `telnet` | SUSE:Linux Enterprise Server 15 SP1-LTSS | All versions | 1.2-150000.3.6.1 | | `telnet` | SUSE:Linux Enterprise Server 15 SP2-BCL | All versions | 1.2-150000.3.6.1 | | `telnet` | SUSE:Linux Enterprise Server 15 SP2-LTSS | All versions | 1.2-150000.3.6.1 | | `telnet` | SUSE:Linux Enterprise Server 15-LTSS | All versions | 1.2-150000.3.6.1 | | `krb5-appl` | SUSE:Linux Enterprise Server for SAP Applications 12 SP4 | All versions | 1.0.3-3.9.1 | | `telnet` | SUSE:Linux Enterprise Server for SAP Applications 12 SP4 | All versions | 1.2-167.10.1 | | `krb5-appl` | SUSE:Linux Enterprise Server for SAP Applications 12 SP5 | All versions | 1.0.3-3.9.1 | | `telnet` | SUSE:Linux Enterprise Server for SAP Applications 12 SP5 | All versions | 1.2-167.10.1 | | `telnet` | SUSE:Linux Enterprise Server for SAP Applications 15 | All versions | 1.2-150000.3.6.1 | | `telnet` | SUSE:Linux Enterprise Server for SAP Applications 15 SP1 | All versions | 1.2-150000.3.6.1 | | `telnet` | SUSE:Linux Enterprise Server for SAP Applications 15 SP2 | All versions | 1.2-150000.3.6.1 | | `telnet` | SUSE:Manager Proxy 4.1 | All versions | 1.2-150000.3.6.1 | | `telnet` | SUSE:Manager Retail Branch Server 4.1 | All versions | 1.2-150000.3.6.1 | | `telnet` | SUSE:Manager Server 4.1 | All versions | 1.2-150000.3.6.1 | | `krb5-appl` | SUSE:OpenStack Cloud 9 | All versions | 1.0.3-3.9.1 | | `telnet` | SUSE:OpenStack Cloud 9 | All versions | 1.2-167.10.1 | | `krb5-appl` | SUSE:OpenStack Cloud Crowbar 9 | All versions | 1.0.3-3.9.1 | | `telnet` | SUSE:OpenStack Cloud Crowbar 9 | All versions | 1.2-167.10.1 | | `telnet` | openSUSE:Leap 15.3 | All versions | 1.2-150000.3.6.1 | Products: Debian Debian Linux, Gnu Inetutils, Mit Kerberos 5, Netkit-Telnet Project Netkit-Telnet. ## How do I fix CVE-2022-39028? Apply the vendor's patch. ## Is CVE-2022-39028 being exploited? There is no known exploitation of CVE-2022-39028 in the wild and no public exploit code. ## Other vulnerabilities in Debian Debian Linux - [CVE-2015-3306](https://insights.sbomify.com/CVE-2015-3306/): ProFTPD Improper Access Control (critical 10.0, exploited in the wild) - [CVE-2025-49113](https://insights.sbomify.com/CVE-2025-49113/): RoundCube Webmail Deserialization of Untrusted Data (critical 9.9, exploited in the wild) - [CVE-2026-24061](https://insights.sbomify.com/CVE-2026-24061/): GNU InetUtils Argument Injection (critical 9.8, exploited in the wild) - [CVE-2025-39682](https://insights.sbomify.com/CVE-2025-39682/): Linux Kernel Improper Check for Unusual or Exceptional Conditions (critical 9.8, exploited in the wild) - [CVE-2024-9680](https://insights.sbomify.com/CVE-2024-9680/): Mozilla Firefox Use-After-Free (critical 9.8, exploited in the wild) ## Fix prompt for AI coding agents ```text Check this codebase for CVE-2022-39028 and fix it if it is affected. What it is: CVE-2022-39028 is a high-severity vulnerability in Debian Debian Linux, published on 30 Aug 2022. 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-2022-39028 in the wild and no public exploit code. Affected product: Debian Debian 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-2022-39028/ (Markdown: https://insights.sbomify.com/CVE-2022-39028/index.md) ``` ## Sources - CVE record: https://www.cve.org/CVERecord?id=CVE-2022-39028 - NVD: https://nvd.nist.gov/vuln/detail/CVE-2022-39028 - OSV: https://osv.dev/vulnerability/CVE-2022-39028 --- From sbomify Insights: https://insights.sbomify.com/CVE-2022-39028/ Summaries are generated and may contain mistakes; the official description above is the record.