# CVE-2024-8508: Unbounded name compression could lead to Denial of Service > Attackers can cause denial of service in Unbound DNS resolver by sending malicious responses with large RRsets, forcing excessive CPU usage during name compression. - **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:** 3 Oct 2024 - **Updated:** 14 Nov 2024 - **Also known as:** ALPINE-CVE-2024-8508, ALSA-2024:11232, ALSA-2025:8047, AZL-49915, AZL-49976, CLSA-2025-1736503760, CLSA-2025-1765901537, CLSA-2025-1765902454, CLSA-2025-1765997462, CLSA-2026-1769424072, DEBIAN-CVE-2024-8508, DLA-3952-1, GHSA-g7cv-x9wx-38gx, GHSA-q2qq-hmj6-3wpp, MGASA-2024-0333, MINI-63xp-c6mr-qcr6, MINI-77fj-98x5-xqwx, MINI-8jcf-533w-c682, MINI-fj9r-4xj9-qf72, MINI-gmgv-8p85-8777, MINI-m9gw-xh58-9vx2, MINI-mw6m-prxp-35m3, OESA-2024-2266, RHSA-2024:11170, RHSA-2024:11232, RHSA-2025:8047, RHSA-2025:8197, RLSA-2024:11232, RLSA-2025:8047, RLSA-2025:8197, RUSTSEC-2026-0119, SUSE-SU-2024:3646-1, SUSE-SU-2024:3647-1, SUSE-SU-2025:20126-1, SUSE-SU-2025:20359-1, UBUNTU-CVE-2024-8508, USN-7080-1, openSUSE-SU-2024:14391-1 ## What is CVE-2024-8508? CVE-2024-8508 is a medium-severity denial of service vulnerability in Debian Debian Linux, published on 3 Oct 2024. An attacker can exploit it over the internet without logging in, with no action from the victim. ### Official description NLnet Labs Unbound up to and including version 1.21.0 contains a vulnerability when handling replies with very large RRsets that it needs to perform name compression for. Malicious upstreams responses with very large RRsets can cause Unbound to spend a considerable time applying name compression to downstream replies. This can lead to degraded performance and eventually denial of service in well orchestrated attacks. The vulnerability can be exploited by a malicious actor querying Unbound for the specially crafted contents of a malicious zone with very large RRsets. Before Unbound replies to the query it will try to apply name compression which was an unbounded operation that could lock the CPU until the whole packet was complete. Unbound version 1.21.1 introduces a hard limit on the number of name compression calculations it is willing to do per packet. Packets that need more compression will result in semi-compressed packets or truncated packets, even on TCP for huge messages, to avoid locking the CPU for long. This change should not affect normal DNS traffic. Weakness: CWE-1284 (Improper Validation of Specified Quantity in Input), CWE-606 (Unchecked Input for Loop Condition) ## Which versions are affected by CVE-2024-8508? 3 open source packages ship an affected version, including hickory-proto. It affects 2 products. | Package | Ecosystem | Affected | Fixed in | | --- | --- | --- | --- | | `hickory-proto` | crates.io | From 0.3.1 | 0.26.1 | | `hickory-proto` | crates.io | From 0.3.1 | 0.26.1 | | `hickory-proto` | crates.io | From 0.3.1 | 0.26.1 | | `python3-unbound` | AlmaLinux:10 | All versions | 1.20.0-10.el10_0 | | `unbound` | AlmaLinux:10 | All versions | 1.20.0-10.el10_0 | | `unbound-anchor` | AlmaLinux:10 | All versions | 1.20.0-10.el10_0 | | `unbound-devel` | AlmaLinux:10 | All versions | 1.20.0-10.el10_0 | | `unbound-dracut` | AlmaLinux:10 | All versions | 1.20.0-10.el10_0 | | `unbound-libs` | AlmaLinux:10 | All versions | 1.20.0-10.el10_0 | | `python3-unbound` | AlmaLinux:9 | All versions | 1.16.2-8.el9_5.1 | | `unbound` | AlmaLinux:9 | All versions | 1.16.2-8.el9_5.1 | | `unbound-devel` | AlmaLinux:9 | All versions | 1.16.2-8.el9_5.1 | | `unbound-libs` | AlmaLinux:9 | All versions | 1.16.2-8.el9_5.1 | | `python3-unbound` | Red Hat:enterprise_linux:10.0 | All versions | 0:1.20.0-10.el10_0 | | `python3-unbound-debuginfo` | Red Hat:enterprise_linux:10.0 | All versions | 0:1.20.0-10.el10_0 | | `unbound` | Red Hat:enterprise_linux:10.0 | All versions | 0:1.20.0-10.el10_0 | | `unbound-anchor` | Red Hat:enterprise_linux:10.0 | All versions | 0:1.20.0-10.el10_0 | | `unbound-anchor-debuginfo` | Red Hat:enterprise_linux:10.0 | All versions | 0:1.20.0-10.el10_0 | | `unbound-debuginfo` | Red Hat:enterprise_linux:10.0 | All versions | 0:1.20.0-10.el10_0 | | `unbound-debugsource` | Red Hat:enterprise_linux:10.0 | All versions | 0:1.20.0-10.el10_0 | | `unbound-devel` | Red Hat:enterprise_linux:10.0 | All versions | 0:1.20.0-10.el10_0 | | `unbound-dracut` | Red Hat:enterprise_linux:10.0 | All versions | 0:1.20.0-10.el10_0 | | `unbound-libs` | Red Hat:enterprise_linux:10.0 | All versions | 0:1.20.0-10.el10_0 | | `unbound-libs-debuginfo` | Red Hat:enterprise_linux:10.0 | All versions | 0:1.20.0-10.el10_0 | | `unbound-utils-debuginfo` | Red Hat:enterprise_linux:10.0 | All versions | 0:1.20.0-10.el10_0 | | `python3-unbound` | Red Hat:enterprise_linux:9::appstream | All versions | 0:1.16.2-18.el9_6 | | `python3-unbound` | Red Hat:enterprise_linux:9::appstream | All versions | 0:1.16.2-8.el9_5.1 | | `python3-unbound-debuginfo` | Red Hat:enterprise_linux:9::appstream | All versions | 0:1.16.2-18.el9_6 | | `python3-unbound-debuginfo` | Red Hat:enterprise_linux:9::appstream | All versions | 0:1.16.2-8.el9_5.1 | | `unbound` | Red Hat:enterprise_linux:9::appstream | All versions | 0:1.16.2-18.el9_6 | | `unbound` | Red Hat:enterprise_linux:9::appstream | All versions | 0:1.16.2-8.el9_5.1 | | `unbound-debuginfo` | Red Hat:enterprise_linux:9::appstream | All versions | 0:1.16.2-18.el9_6 | | `unbound-debuginfo` | Red Hat:enterprise_linux:9::appstream | All versions | 0:1.16.2-8.el9_5.1 | | `unbound-debugsource` | Red Hat:enterprise_linux:9::appstream | All versions | 0:1.16.2-18.el9_6 | | `unbound-debugsource` | Red Hat:enterprise_linux:9::appstream | All versions | 0:1.16.2-8.el9_5.1 | | `unbound-dracut` | Red Hat:enterprise_linux:9::appstream | All versions | 0:1.16.2-18.el9_6 | | `unbound-libs` | Red Hat:enterprise_linux:9::appstream | All versions | 0:1.16.2-18.el9_6 | | `unbound-libs` | Red Hat:enterprise_linux:9::appstream | All versions | 0:1.16.2-8.el9_5.1 | | `unbound-libs-debuginfo` | Red Hat:enterprise_linux:9::appstream | All versions | 0:1.16.2-18.el9_6 | | `unbound-libs-debuginfo` | Red Hat:enterprise_linux:9::appstream | All versions | 0:1.16.2-8.el9_5.1 | Products: Debian Debian Linux, Nlnetlabs Unbound. ## How do I fix CVE-2024-8508? Upgrade hickory-proto to 0.26.1 or later. ## Is CVE-2024-8508 being exploited? There is no known exploitation of CVE-2024-8508 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-2024-8508 and fix it if it is affected. What it is: CVE-2024-8508 is a medium-severity denial of service vulnerability in Debian Debian Linux, published on 3 Oct 2024. 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-2024-8508 in the wild and no public exploit code. Affected packages and fixed versions: - hickory-proto (crates.io): affected from 0.3.1; fixed in 0.26.1 - hickory-proto (crates.io): affected from 0.3.1; fixed in 0.26.1 - hickory-proto (crates.io): affected from 0.3.1; fixed in 0.26.1 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-2024-8508/ (Markdown: https://insights.sbomify.com/CVE-2024-8508/index.md) ``` ## Sources - CVE record: https://www.cve.org/CVERecord?id=CVE-2024-8508 - NVD: https://nvd.nist.gov/vuln/detail/CVE-2024-8508 - OSV: https://osv.dev/vulnerability/CVE-2024-8508 --- From sbomify Insights: https://insights.sbomify.com/CVE-2024-8508/ Summaries are generated and may contain mistakes; the official description above is the record.