# CVE-2026-5072: ptp: Potential Denial of Service via PTP Interval Shift

> Remote attackers can crash Zephyr RTOS devices by sending crafted PTP messages that trigger undefined behavior via invalid bitwise shifts.

- **Severity:** Medium 6.5 (`CVSS:3.1/AV:A/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:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 22 May 2026
- **Updated:** 15 Oct 2026
- **Also known as:** GHSA-3v98-458v-388r

## What is CVE-2026-5072?

CVE-2026-5072 is a medium-severity vulnerability in Zephyrproject Zephyr, published on 22 May 2026. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

A bitwise shift vulnerability in Zephyr's PTP subsystem allows a remote attacker to cause undefined behavior and potential system crashes. An attacker sends a crafted PTP_MSG_MANAGEMENT message to set an unvalidated negative log_announce_interval value in the port's data set. When a subsequent PTP_MSG_ANNOUNCE message is processed, port_timer_set_timeout_random computes a timeout as NSEC_PER_SEC >> -log_seconds; if the attacker-supplied value is sufficiently negative (e.g., -127), the shift amount exceeds the 64-bit integer width, triggering undefined behavior in C. This can cause a system crash via a compiler-generated illegal instruction trap on some architectures, or produce an erroneous zero timeout leading to resource starvation loops or other logical errors.

Weakness: CWE-1335 (Incorrect Bitwise Shift of Integer)

## Which versions are affected by CVE-2026-5072?

It affects 1 product.


Products: Zephyrproject Zephyr.

## How do I fix CVE-2026-5072?

No fix has been published for CVE-2026-5072 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-5072 being exploited?

There is no known exploitation of CVE-2026-5072 in the wild and no public exploit code.

## Other vulnerabilities in Zephyrproject Zephyr

- [CVE-2026-5067](https://insights.sbomify.com/CVE-2026-5067/): Out-of-bounds read/write in HTTP WebSocket upgrade via non-null-terminated Sec-WebSocket-Key (critical 9.8)
- [CVE-2022-3806](https://insights.sbomify.com/CVE-2022-3806/): Bluetooth HCI Error Handling Double Free (critical 9.8)
- [CVE-2017-14199](https://insights.sbomify.com/CVE-2017-14199/): Memory corruption in getaddrinfo (critical 9.8)
- [CVE-2018-1000800](https://insights.sbomify.com/CVE-2018-1000800/): Null dereference in n/a (critical 9.8)
- [CVE-2021-3329](https://insights.sbomify.com/CVE-2021-3329/): DOS: Incorrect handling of the initial HCI ACL_MTU handshake packet leads to crash of bluetooth host layer (critical 9.6)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-5072 and fix it if it is affected.

What it is: CVE-2026-5072 is a medium-severity vulnerability in Zephyrproject Zephyr, published on 22 May 2026. 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-2026-5072 in the wild and no public exploit code.

Affected product: Zephyrproject Zephyr. 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-2026-5072/ (Markdown: https://insights.sbomify.com/CVE-2026-5072/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-5072
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-5072
- OSV: https://osv.dev/vulnerability/CVE-2026-5072

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-5072/
Summaries are generated and may contain mistakes; the official description above is the record.