CVE-2026-54580

What it is

mport is the MidnightBSD Package Manager. Prior to 2.7.8, libmport/util.c did not make every truncated, corrupt, or failed zstd stream fatal in mport_decompress_zstd(), and libmport/fetch.c did not consistently propagate those failures to index-fetch callers. A malicious or faulty mirror could supply compressed package index data that caused ZSTD_decompressStream() or an output write to fail while leaving partial index output available for later use, resulting in package-index integrity loss or denial of service. This issue is fixed in version 2.7.8.

At a glance

Exploitability

Can be exploited over the network without logging in. High risk of service disruption.

Exploit odds

0.3% chance of exploitation in the next 30 days (EPSS).

Fix

A patch, advisory or fixed version is referenced. Upgrade or apply it.

Timeline

1. 2026-09-17 17:16 UTC PublishedDisclosed publicly on CVE.org and NVD
2. 2026-09-24 21:17 UTC Last updatedMost recent change to the record

Details

Published

2026-09-17 17:16 UTC

Last modified

2026-09-24 21:17 UTC

Exploit probability

0.3% · EPSS, next 30 days

Weakness

CWE-354

Record status

Deferred

Attack profile CVSS 4.0 · 8.3

Attack vector

Network

Complexity

Low

Attack requirements

Present

Privileges needed

None

User interaction

None

Confidentiality

None

Integrity

Low

Availability

High