# CVE-2023-46728: SQUID-2021:8 Denial of Service in Gopher gateway > A NULL pointer dereference in Squid's Gopher gateway allows remote attackers to cause a denial of service via crafted responses. - **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:** 6 Nov 2023 - **Updated:** 3 Nov 2025 - **Also known as:** AZL-31941, CLSA-2023-1702420408, CLSA-2023-1702420474, CLSA-2023-1702495324, CLSA-2023-1702495594, CLSA-2023-1702495796, CLSA-2023-1702495907, CLSA-2023-1702496332, CLSA-2023-1702496473, DEBIAN-CVE-2023-46728, GHSA-cg5h-v6vc-w33f, SUSE-SU-2023:4544-1, SUSE-SU-2023:4545-1, SUSE-SU-2023:4589-1, UBUNTU-CVE-2023-46728 ## What is CVE-2023-46728? CVE-2023-46728 is a high-severity vulnerability in Squid-Cache Squid, published on 6 Nov 2023. An attacker can exploit it over the internet without logging in, with no action from the victim. ### Official description Squid is a caching proxy for the Web supporting HTTP, HTTPS, FTP, and more. Due to a NULL pointer dereference bug Squid is vulnerable to a Denial of Service attack against Squid's Gopher gateway. The gopher protocol is always available and enabled in Squid prior to Squid 6.0.1. Responses triggering this bug are possible to be received from any gopher server, even those without malicious intent. Gopher support has been removed in Squid version 6.0.1. Users are advised to upgrade. Users unable to upgrade should reject all gopher URL requests. Weakness: CWE-476 (NULL Pointer Dereference) ## Which versions are affected by CVE-2023-46728? It affects 1 product. | Package | Ecosystem | Affected | Fixed in | | --- | --- | --- | --- | | `squid` | SUSE:Enterprise Storage 7.1 | All versions | 4.17-150000.5.41.1 | | `squid` | SUSE:Linux Enterprise High Performance Computing 15 SP1-LTSS | All versions | 4.17-150000.5.41.1 | | `squid` | SUSE:Linux Enterprise High Performance Computing 15 SP2-LTSS | All versions | 4.17-150000.5.41.1 | | `squid` | SUSE:Linux Enterprise High Performance Computing 15 SP3-ESPOS | All versions | 4.17-150000.5.41.1 | | `squid` | SUSE:Linux Enterprise High Performance Computing 15 SP3-LTSS | All versions | 4.17-150000.5.41.1 | | `squid` | SUSE:Linux Enterprise Module for Server Applications 15 SP4 | All versions | 5.7-150400.3.15.1 | | `squid` | SUSE:Linux Enterprise Module for Server Applications 15 SP5 | All versions | 5.7-150400.3.15.1 | | `squid` | SUSE:Linux Enterprise Server 12 SP5 | All versions | 4.17-4.33.1 | | `squid` | SUSE:Linux Enterprise Server 15 SP1-LTSS | All versions | 4.17-150000.5.41.1 | | `squid` | SUSE:Linux Enterprise Server 15 SP2-LTSS | All versions | 4.17-150000.5.41.1 | | `squid` | SUSE:Linux Enterprise Server 15 SP3-LTSS | All versions | 4.17-150000.5.41.1 | | `squid` | SUSE:Linux Enterprise Server for SAP Applications 12 SP5 | All versions | 4.17-4.33.1 | | `squid` | SUSE:Linux Enterprise Server for SAP Applications 15 SP1 | All versions | 4.17-150000.5.41.1 | | `squid` | SUSE:Linux Enterprise Server for SAP Applications 15 SP2 | All versions | 4.17-150000.5.41.1 | | `squid` | SUSE:Linux Enterprise Server for SAP Applications 15 SP3 | All versions | 4.17-150000.5.41.1 | | `squid` | openSUSE:Leap 15.4 | All versions | 5.7-150400.3.15.1 | | `squid` | openSUSE:Leap 15.5 | All versions | 5.7-150400.3.15.1 | Products: Squid-Cache Squid. ## How do I fix CVE-2023-46728? Upgrade to a fixed version. ## Is CVE-2023-46728 being exploited? There is no known exploitation of CVE-2023-46728 in the wild and no public exploit code. ## Other vulnerabilities in Squid-Cache Squid - [CVE-2025-62168](https://insights.sbomify.com/CVE-2025-62168/): Squid vulnerable to information disclosure via authentication credential leakage in error handling (critical 10.0) - [CVE-2025-54574](https://insights.sbomify.com/CVE-2025-54574/): Squid's URN Handling can lead to Buffer Overflow (critical 9.3) - [CVE-2026-33526](https://insights.sbomify.com/CVE-2026-33526/): Squid vulnerable to Denial of Service in ICP Request handling (critical 9.2) - [CVE-2026-32748](https://insights.sbomify.com/CVE-2026-32748/): Squid has Denial of Service in ICP Response handling (high 8.7) - [CVE-2023-50269](https://insights.sbomify.com/CVE-2023-50269/): SQUID-2023:10 Denial of Service in HTTP Request parsing (high 8.6) ## Fix prompt for AI coding agents ```text Check this codebase for CVE-2023-46728 and fix it if it is affected. What it is: CVE-2023-46728 is a high-severity vulnerability in Squid-Cache Squid, published on 6 Nov 2023. 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-2023-46728 in the wild and no public exploit code. Affected product: Squid-Cache Squid. 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-2023-46728/ (Markdown: https://insights.sbomify.com/CVE-2023-46728/index.md) ``` ## Sources - CVE record: https://www.cve.org/CVERecord?id=CVE-2023-46728 - NVD: https://nvd.nist.gov/vuln/detail/CVE-2023-46728 - OSV: https://osv.dev/vulnerability/CVE-2023-46728 --- From sbomify Insights: https://insights.sbomify.com/CVE-2023-46728/ Summaries are generated and may contain mistakes; the official description above is the record.