# CVE-2026-71402: wicked: out-of-bounds read in the DHCPv4 option parser due to payload length taken from the IP total length

> An attacker on the same network can trigger an out-of-bounds read in wicked's DHCP client, potentially leaking heap memory contents into lease fields.

- **Severity:** Medium 5.3 (`CVSS:4.0/AV:A/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N`)
- **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:** 27 Aug 2026
- **Updated:** 27 Aug 2026
- **Also known as:** GHSA-qwmv-r6fq-g9r3

## What is CVE-2026-71402?

CVE-2026-71402 is a medium-severity vulnerability in SUSE wicked, published on 27 Aug 2026. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

An out-of-bounds read was found in the DHCPv4 packet capture code of wicked. ni_capture_inspect_udp_header() in src/capture.c reports the IP total length as the payload length instead of the length of the remaining UDP payload. Consequently, the DHCP option walker in the DHCPv4 client (wickedd-dhcp4) reads up to ihl + 8 bytes — at most 68 bytes — past the end of the 1500-byte packet receive buffer. An unauthenticated attacker on the same network who sends a crafted DHCP/UDP packet can make the client parse adjacent heap memory as DHCP options, so that heap contents such as allocator metadata or pointer values can be interpreted into lease fields. The over-read is bounded to 68 bytes; no memory write, no attacker control over the adjacent bytes and no remote exfiltration primitive has been demonstrated. This issue affects wicked up to and including version 0.6.80.

Weakness: CWE-130 (Improper Handling of Length Parameter Inconsistency), CWE-125 (Out-of-bounds Read)

## Which versions are affected by CVE-2026-71402?


## How do I fix CVE-2026-71402?

Apply the vendor's patch.

## Is CVE-2026-71402 being exploited?

There is no known exploitation of CVE-2026-71402 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-71402 and fix it if it is affected.

What it is: CVE-2026-71402 is a medium-severity vulnerability in SUSE wicked, published on 27 Aug 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-2026-71402 in the wild and no public exploit code.

Affected product: SUSE wicked. 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-2026-71402/ (Markdown: https://insights.sbomify.com/CVE-2026-71402/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-71402
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-71402
- OSV: https://osv.dev/vulnerability/CVE-2026-71402

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-71402/
Summaries are generated and may contain mistakes; the official description above is the record.