Vulnerability · Published Sep 17, 2026 · Assigned by GitHub_M

CVE-2026-54583mport package bundle downloads allow unsafe destination filenames

High 8.3

In plain English

A high-severity path traversal in mport from MidnightBSD. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.5% (higher than 46% of all known vulnerabilities).

Severity (CVSS 4.0)8.3High

Exploit odds (30 days)0.5%top 54.4% of all CVEs

Exploited in the wildNo reportsCISA SSVC: none

Attack toolingNoneno public tooling known

Official description

mport is the MidnightBSD Package Manager. Prior to 2.7.8, libmport/fetch.c did not consistently reject empty, dot, dot-dot, or slash-containing bundle filenames before composing package download and write paths. Malicious package index data could place an unsafe value in indexEntry->bundlefile, and the missing is_valid_bundle_filename() checks allowed downloaded package data to be written outside the intended cache location or to an unsafe destination name. This issue is fixed in version 2.7.8.

Affected products (as reported)

Vendor	Product	Versions
MidnightBSD	mport	< 2.7.8

Weakness: CWE-22, CWE-73 · Vector: CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:H/VA:L/SC:N/SI:N/SA:N

References

https://github.com/MidnightBSD/mport/security/advisories/GHSA-mr62-mqwj-vhh3 x_refsource_CONFIRM
https://github.com/MidnightBSD/mport/pull/125 x_refsource_MISC
https://github.com/MidnightBSD/mport/commit/cad959d47bc79a62b6a7163800fbfe35633e7cf8 x_refsource_MISC
https://github.com/MidnightBSD/mport/releases/tag/2.7.8 x_refsource_MISC