# CVE-2021-41229: Memory leak in BlueZ

> An attacker can cause a memory leak and crash the Bluetooth service by continuously sending SDP packets to a Linux device using BlueZ.

- **Severity:** Medium 4.3 (`CVSS:3.1/AV:A/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:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 12 Nov 2021
- **Updated:** 4 Nov 2025
- **Also known as:** ALSA-2022:2081, DEBIAN-CVE-2021-41229, GHSA-3fqg-r8j5-f5xq, OESA-2022-1763, RHSA-2022:2081, RLSA-2022:2081, SUSE-SU-2023:3238-1, SUSE-SU-2023:3240-1, SUSE-SU-2023:3689-1, UBUNTU-CVE-2021-41229

## What is CVE-2021-41229?

CVE-2021-41229 is a medium-severity denial of service vulnerability in Debian Debian Linux, published on 12 Nov 2021. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

BlueZ is a Bluetooth protocol stack for Linux. In affected versions a vulnerability exists in sdp_cstate_alloc_buf which allocates memory which will always be hung in the singly linked list of cstates and will not be freed. This will cause a memory leak over time. The data can be a very large object, which can be caused by an attacker continuously sending sdp packets and this may cause the service of the target device to crash.

Weakness: CWE-401 (Missing Release of Memory after Effective Lifetime), CWE-400 (Uncontrolled Resource Consumption)

## Which versions are affected by CVE-2021-41229?

It affects 2 products.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `bluez` | AlmaLinux:8 | All versions | 5.56-3.el8 |
| `bluez-cups` | AlmaLinux:8 | All versions | 5.56-3.el8 |
| `bluez-hid2hci` | AlmaLinux:8 | All versions | 5.56-3.el8 |
| `bluez-libs` | AlmaLinux:8 | All versions | 5.56-3.el8 |
| `bluez-libs-devel` | AlmaLinux:8 | All versions | 5.56-3.el8 |
| `bluez-obexd` | AlmaLinux:8 | All versions | 5.56-3.el8 |
| `bluez-cups` | Red Hat:enterprise_linux:8::appstream | All versions | 0:5.56-3.el8 |
| `bluez-cups-debuginfo` | Red Hat:enterprise_linux:8::appstream | All versions | 0:5.56-3.el8 |
| `bluez-debuginfo` | Red Hat:enterprise_linux:8::appstream | All versions | 0:5.56-3.el8 |
| `bluez-debugsource` | Red Hat:enterprise_linux:8::appstream | All versions | 0:5.56-3.el8 |
| `bluez-hid2hci-debuginfo` | Red Hat:enterprise_linux:8::appstream | All versions | 0:5.56-3.el8 |
| `bluez-libs-debuginfo` | Red Hat:enterprise_linux:8::appstream | All versions | 0:5.56-3.el8 |
| `bluez-obexd-debuginfo` | Red Hat:enterprise_linux:8::appstream | All versions | 0:5.56-3.el8 |
| `bluez` | Red Hat:enterprise_linux:8::baseos | All versions | 0:5.56-3.el8 |
| `bluez-cups-debuginfo` | Red Hat:enterprise_linux:8::baseos | All versions | 0:5.56-3.el8 |
| `bluez-debuginfo` | Red Hat:enterprise_linux:8::baseos | All versions | 0:5.56-3.el8 |
| `bluez-debugsource` | Red Hat:enterprise_linux:8::baseos | All versions | 0:5.56-3.el8 |
| `bluez-hid2hci` | Red Hat:enterprise_linux:8::baseos | All versions | 0:5.56-3.el8 |
| `bluez-hid2hci-debuginfo` | Red Hat:enterprise_linux:8::baseos | All versions | 0:5.56-3.el8 |
| `bluez-libs` | Red Hat:enterprise_linux:8::baseos | All versions | 0:5.56-3.el8 |
| `bluez-libs-debuginfo` | Red Hat:enterprise_linux:8::baseos | All versions | 0:5.56-3.el8 |
| `bluez-obexd` | Red Hat:enterprise_linux:8::baseos | All versions | 0:5.56-3.el8 |
| `bluez-obexd-debuginfo` | Red Hat:enterprise_linux:8::baseos | All versions | 0:5.56-3.el8 |
| `bluez-cups-debuginfo` | Red Hat:enterprise_linux:8::crb | All versions | 0:5.56-3.el8 |
| `bluez-debuginfo` | Red Hat:enterprise_linux:8::crb | All versions | 0:5.56-3.el8 |
| `bluez-debugsource` | Red Hat:enterprise_linux:8::crb | All versions | 0:5.56-3.el8 |
| `bluez-hid2hci-debuginfo` | Red Hat:enterprise_linux:8::crb | All versions | 0:5.56-3.el8 |
| `bluez-libs-debuginfo` | Red Hat:enterprise_linux:8::crb | All versions | 0:5.56-3.el8 |
| `bluez-libs-devel` | Red Hat:enterprise_linux:8::crb | All versions | 0:5.56-3.el8 |
| `bluez-obexd-debuginfo` | Red Hat:enterprise_linux:8::crb | All versions | 0:5.56-3.el8 |
| `bluez` | Rocky Linux:8 | All versions | 0:5.56-3.el8 |
| `bluez` | SUSE:Linux Enterprise Micro 5.3 | All versions | 5.62-150400.4.16.1 |
| `bluez` | SUSE:Linux Enterprise Micro 5.4 | All versions | 5.62-150400.4.16.1 |
| `bluez` | SUSE:Linux Enterprise Module for Basesystem 15 SP4 | All versions | 5.62-150400.4.16.1 |
| `bluez` | SUSE:Linux Enterprise Module for Desktop Applications 15 SP4 | All versions | 5.62-150400.4.16.1 |
| `bluez` | SUSE:Linux Enterprise Server 12 SP5 | All versions | 5.13-5.42.2 |
| `bluez` | SUSE:Linux Enterprise Server for SAP Applications 12 SP5 | All versions | 5.13-5.42.2 |
| `bluez` | SUSE:Linux Enterprise Software Development Kit 12 SP5 | All versions | 5.13-5.42.2 |
| `bluez` | SUSE:Linux Enterprise Workstation Extension 12 SP5 | All versions | 5.13-5.42.2 |
| `bluez` | SUSE:Linux Enterprise Workstation Extension 15 SP4 | All versions | 5.62-150400.4.16.1 |

Products: Bluez Bluez, Debian Debian Linux.

## How do I fix CVE-2021-41229?

Apply the vendor's patch.

## Is CVE-2021-41229 being exploited?

There is no known exploitation of CVE-2021-41229 in the wild and no public exploit code.

## Other vulnerabilities in Debian Debian 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-2021-41229 and fix it if it is affected.

What it is: CVE-2021-41229 is a medium-severity denial of service vulnerability in Debian Debian Linux, published on 12 Nov 2021. 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-2021-41229 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-2021-41229/ (Markdown: https://insights.sbomify.com/CVE-2021-41229/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2021-41229
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2021-41229
- OSV: https://osv.dev/vulnerability/CVE-2021-41229

---
From sbomify Insights: https://insights.sbomify.com/CVE-2021-41229/
Summaries are generated and may contain mistakes; the official description above is the record.