# CVE-2020-0556: Privilege escalation in BlueZ > An unauthenticated attacker with adjacent access can escalate privileges or cause denial of service in the BlueZ Bluetooth subsystem. - **Severity:** High 7.1 (`CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:L`) - **Exploited in the wild:** Not known - **Login needed:** Not needed - **Attackable:** Local or same network only - **Victim action needed:** Not needed - **Fix available:** Yes - **Published:** 12 Mar 2020 - **Updated:** 4 Aug 2024 - **Also known as:** ALPINE-CVE-2020-0556, CLEANSTART-2026-VA16000, DEBIAN-CVE-2020-0556, DLA-2240-1, DSA-4647-1, GHSA-xjj6-3w9q-h5xv, RHSA-2020:4001, RHSA-2020:4481, SUSE-SU-2020:0918-1, SUSE-SU-2020:3516-1, UBUNTU-CVE-2020-0556, openSUSE-SU-2020:0479-1, openSUSE-SU-2020:0872-1 ## What is CVE-2020-0556? CVE-2020-0556 is a high-severity vulnerability in Canonical Ubuntu Linux, published on 12 Mar 2020. It can only be exploited from the same machine or local network, with no action from the victim. ### Official description Improper access control in subsystem for BlueZ before version 5.54 may allow an unauthenticated user to potentially enable escalation of privilege and denial of service via adjacent access ## Which versions are affected by CVE-2020-0556? It affects 4 products. | Package | Ecosystem | Affected | Fixed in | | --- | --- | --- | --- | | `bluez` | Red Hat:enterprise_linux:7::client | All versions | 0:5.44-7.el7 | | `bluez-cups` | Red Hat:enterprise_linux:7::client | All versions | 0:5.44-7.el7 | | `bluez-debuginfo` | Red Hat:enterprise_linux:7::client | All versions | 0:5.44-7.el7 | | `bluez-hid2hci` | Red Hat:enterprise_linux:7::client | All versions | 0:5.44-7.el7 | | `bluez-libs` | Red Hat:enterprise_linux:7::client | All versions | 0:5.44-7.el7 | | `bluez-libs-devel` | Red Hat:enterprise_linux:7::client | All versions | 0:5.44-7.el7 | | `bluez` | Red Hat:enterprise_linux:7::computenode | All versions | 0:5.44-7.el7 | | `bluez-cups` | Red Hat:enterprise_linux:7::computenode | All versions | 0:5.44-7.el7 | | `bluez-debuginfo` | Red Hat:enterprise_linux:7::computenode | All versions | 0:5.44-7.el7 | | `bluez-hid2hci` | Red Hat:enterprise_linux:7::computenode | All versions | 0:5.44-7.el7 | | `bluez-libs` | Red Hat:enterprise_linux:7::computenode | All versions | 0:5.44-7.el7 | | `bluez-libs-devel` | Red Hat:enterprise_linux:7::computenode | All versions | 0:5.44-7.el7 | | `bluez` | Red Hat:enterprise_linux:7::server | All versions | 0:5.44-7.el7 | | `bluez-cups` | Red Hat:enterprise_linux:7::server | All versions | 0:5.44-7.el7 | | `bluez-debuginfo` | Red Hat:enterprise_linux:7::server | All versions | 0:5.44-7.el7 | | `bluez-hid2hci` | Red Hat:enterprise_linux:7::server | All versions | 0:5.44-7.el7 | | `bluez-libs` | Red Hat:enterprise_linux:7::server | All versions | 0:5.44-7.el7 | | `bluez-libs-devel` | Red Hat:enterprise_linux:7::server | All versions | 0:5.44-7.el7 | | `bluez` | Red Hat:enterprise_linux:7::workstation | All versions | 0:5.44-7.el7 | | `bluez-cups` | Red Hat:enterprise_linux:7::workstation | All versions | 0:5.44-7.el7 | | `bluez-debuginfo` | Red Hat:enterprise_linux:7::workstation | All versions | 0:5.44-7.el7 | | `bluez-hid2hci` | Red Hat:enterprise_linux:7::workstation | All versions | 0:5.44-7.el7 | | `bluez-libs` | Red Hat:enterprise_linux:7::workstation | All versions | 0:5.44-7.el7 | | `bluez-libs-devel` | Red Hat:enterprise_linux:7::workstation | All versions | 0:5.44-7.el7 | | `bluez-cups` | Red Hat:enterprise_linux:8::appstream | All versions | 0:5.50-4.el8 | | `bluez-cups-debuginfo` | Red Hat:enterprise_linux:8::appstream | All versions | 0:5.50-4.el8 | | `bluez-debuginfo` | Red Hat:enterprise_linux:8::appstream | All versions | 0:5.50-4.el8 | | `bluez-debugsource` | Red Hat:enterprise_linux:8::appstream | All versions | 0:5.50-4.el8 | | `bluez-hid2hci-debuginfo` | Red Hat:enterprise_linux:8::appstream | All versions | 0:5.50-4.el8 | | `bluez-libs-debuginfo` | Red Hat:enterprise_linux:8::appstream | All versions | 0:5.50-4.el8 | | `bluez-obexd-debuginfo` | Red Hat:enterprise_linux:8::appstream | All versions | 0:5.50-4.el8 | | `bluez` | Red Hat:enterprise_linux:8::baseos | All versions | 0:5.50-4.el8 | | `bluez-cups-debuginfo` | Red Hat:enterprise_linux:8::baseos | All versions | 0:5.50-4.el8 | | `bluez-debuginfo` | Red Hat:enterprise_linux:8::baseos | All versions | 0:5.50-4.el8 | | `bluez-debugsource` | Red Hat:enterprise_linux:8::baseos | All versions | 0:5.50-4.el8 | | `bluez-hid2hci` | Red Hat:enterprise_linux:8::baseos | All versions | 0:5.50-4.el8 | | `bluez-hid2hci-debuginfo` | Red Hat:enterprise_linux:8::baseos | All versions | 0:5.50-4.el8 | | `bluez-libs` | Red Hat:enterprise_linux:8::baseos | All versions | 0:5.50-4.el8 | | `bluez-libs-debuginfo` | Red Hat:enterprise_linux:8::baseos | All versions | 0:5.50-4.el8 | | `bluez-obexd` | Red Hat:enterprise_linux:8::baseos | All versions | 0:5.50-4.el8 | Products: Bluez Bluez, Canonical Ubuntu Linux, Debian Debian Linux, Opensuse Leap. ## How do I fix CVE-2020-0556? Upgrade to a fixed version. ## Is CVE-2020-0556 being exploited? There is no known exploitation of CVE-2020-0556 in the wild and no public exploit code. ## Other vulnerabilities in Canonical Ubuntu Linux - [CVE-2021-43400](https://insights.sbomify.com/CVE-2021-43400/): Use after free in n/a (critical 9.1) - [CVE-2024-8805](https://insights.sbomify.com/CVE-2024-8805/): BlueZ HID over GATT Profile Improper Access Control Remote Code Execution Vulnerability (high 8.8) - [CVE-2022-39176](https://insights.sbomify.com/CVE-2022-39176/): Information disclosure in n/a (high 8.8) - [CVE-2022-39177](https://insights.sbomify.com/CVE-2022-39177/): Denial of service in n/a (high 8.8) - [CVE-2022-0204](https://insights.sbomify.com/CVE-2022-0204/): Memory corruption in bluez (high 8.8) ## Fix prompt for AI coding agents ```text Check this codebase for CVE-2020-0556 and fix it if it is affected. What it is: CVE-2020-0556 is a high-severity vulnerability in Canonical Ubuntu Linux, published on 12 Mar 2020. It can only be exploited from the same machine or local network, with no action from the victim. Exploitation: There is no known exploitation of CVE-2020-0556 in the wild and no public exploit code. Affected product: Canonical Ubuntu 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-2020-0556/ (Markdown: https://insights.sbomify.com/CVE-2020-0556/index.md) ``` ## Sources - CVE record: https://www.cve.org/CVERecord?id=CVE-2020-0556 - NVD: https://nvd.nist.gov/vuln/detail/CVE-2020-0556 - OSV: https://osv.dev/vulnerability/CVE-2020-0556 --- From sbomify Insights: https://insights.sbomify.com/CVE-2020-0556/ Summaries are generated and may contain mistakes; the official description above is the record.