# CVE-2026-54579: mport mirror-selection ping accepts insufficiently validated ICMP replies

> A network attacker can cause an out-of-bounds read and influence mirror selection in MidnightBSD's package manager by sending spoofed ICMP replies.

- **Severity:** Low 2.3 (`CVSS:4.0/AV:A/AC:L/AT:P/PR:N/UI:N/VC:N/VI:L/VA:L/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:** No
- **Published:** 17 Sep 2026
- **Updated:** 24 Sep 2026
- **Also known as:** GHSA-qc2f-2j7j-m3r7

## What is CVE-2026-54579?

CVE-2026-54579 is a low-severity memory corruption vulnerability in MidnightBSD mport, published on 17 Sep 2026. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

mport is the MidnightBSD Package Manager. Prior to 2.7.8, ping() in libmport/ping.c accepted ICMP replies without validating icmp_id or icmp_seq and parsed the reply using a fixed IP-header offset instead of ip_hl. A network attacker able to inject or spoof visible ICMP replies could influence mirror latency selection, while a malformed packet carrying IP options could shift the ICMP header and trigger an out-of-bounds read. This issue is fixed in version 2.7.8.

Weakness: CWE-345 (Insufficient Verification of Data Authenticity), CWE-125 (Out-of-bounds Read)

## Which versions are affected by CVE-2026-54579?


## How do I fix CVE-2026-54579?

No fix has been published for CVE-2026-54579 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-54579 being exploited?

There is no known exploitation of CVE-2026-54579 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-54579 and fix it if it is affected.

What it is: CVE-2026-54579 is a low-severity memory corruption vulnerability in MidnightBSD mport, published on 17 Sep 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-2026-54579 in the wild and no public exploit code.

Affected product: MidnightBSD mport. 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-2026-54579/ (Markdown: https://insights.sbomify.com/CVE-2026-54579/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-54579
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-54579
- OSV: https://osv.dev/vulnerability/CVE-2026-54579

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-54579/
Summaries are generated and may contain mistakes; the official description above is the record.