CVE-2026-54576

MEDIUMPre-NVD 5.85.8—
EchelonGraph scoreMEDIUM confidence

This medium-severity CVE scores 5.8 under a secondary CVSS source (NVD's own analysis pending). EPSS exploit probability: 0.1%, top 99% of all CVEs by exploit prediction. GitHub Security Advisory data not yet ingested — confidence will rise once GHSA publishes (typical lag: hours to days for open-source ecosystem CVEs; never for infrastructure-only CVEs).

Triggered by: NVD CVSS baseline
Sources: epss, secondary
Trending — 3 sources updated this week
5.8EG
EchelonGraph verdictMonitorLow exploitation likelihood right now — keep watching.
  • Lower severity and no public exploit yet
CISA-KEV: Not listedEPSS PROB: 0%CVSS: 5.8Exploit: None knownExposed: 0

No vendor fix yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for a patch.

mport is the MidnightBSD Package Manager. Prior to 2.7.8, do_actual_install() in libmport/bundle_read_install_pkg.c used path-based lstat(), chown(), stat(), and chmod() operations while installing package files. A local attacker with write access to a target directory could replace a checked file with a symlink before privileged ownership or mode changes were applied, redirecting those changes to an attacker-selected path and compromising filesystem integrity or permissions. This issue is fixed in version 2.7.8.

CVSS v3
5.8
EG Score
5.8(medium)
EG Risk
26(Track)
EG Risk 26/100SSVC: Track

EG Risk is EchelonGraph's 0–100 priority score: it fuses intrinsic severity with real-world exploitation and automatability so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner. Distinct from the 0–10 EG Score (severity).

How it’s computed
Severity58% × 45%
Exploitation0% × 40%
Automatability0% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
0%
EPSS %ILE
1%
KEV
Not listed

Published

September 17, 2026

Last Modified

September 18, 2026

Advisory Details (4)

Auto-updated Sep 17, 2026
Patch available. Sources: github, github_pr, github_commit, github_release.
github_release Patch Available

mport 2.7.8

Patch available: MidnightBSD/mport 2.7.8

https://github.com/MidnightBSD/mport/releases/tag/2.7.8
github_commit Patch Available

commit 4676ac05b105 (MidnightBSD/mport)

Patch available: MidnightBSD/mport 2.7.8 (contains commit 4676ac05b105)

https://github.com/MidnightBSD/mport/commit/4676ac05b1056b54a3d38d03ae8a478bf12c9abe
github_pr Patch Available

install: close symlink TOCTOU on file chown/chmod

Patch available: MidnightBSD/mport 2.7.8 (PR #150 merged 2026-05-31)

https://github.com/MidnightBSD/mport/pull/150
github Patch Available

mport package installation has symlink TOCTOU in chown and chmod handling · Advisory · MidnightBSD/mport · GitHub

Affected: 2.7.8

https://github.com/MidnightBSD/mport/security/advisories/GHSA-23g3-7fv3-3ccf

Weakness Classification(2)

MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.

Data Freshness Timeline

(refreshed 7× in last 7d / 7× in last 30d)

Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.

  1. 2026-09-19 13:44 UTCEG score recompute
  2. 2026-09-18 19:28 UTCEPSS rescore
  3. 2026-09-18 15:26 UTCEG score recompute
  4. 2026-09-18 14:54 UTCEG score recompute
  5. 2026-09-17 17:35 UTCEG score recompute
  6. 2026-09-17 17:07 UTCEG score recompute
  7. 2026-09-17 17:04 UTCMITRE cvelistV5first tracked

Related CVEs(same CWE)

Frequently asked(5)

What is CVE-2026-54576?
CVE-2026-54576 is a medium vulnerability published on September 17, 2026. mport is the MidnightBSD Package Manager. Prior to 2.7.8, doactualinstall() in libmport/bundlereadinstall_pkg.c used path-based lstat(), chown(), stat(), and chmod() operations while installing package files. A local attacker with write access to a target directory could replace a checked file with…
When was CVE-2026-54576 disclosed?
CVE-2026-54576 was first published in the National Vulnerability Database on September 17, 2026, with the most recent update on September 18, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-54576 actively exploited?
CVE-2026-54576 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0% probability of exploitation in the next 30 days, which ranks it in the top 99.0% of all scored CVEs.
What is the CVSS score of CVE-2026-54576?
CVE-2026-54576 has a CVSS v3 base score of 5.8 (NVD).
How do I remediate CVE-2026-54576?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-54576, EchelonGraph cross-links them in the Vendor Advisories panel below — those typically contain the canonical remediation steps, fixed version numbers, and any vendor-specific mitigations.

Dependency Blast Radius

Explore the affected products and dependency analysis for CVE-2026-54576

Explore →

Is Your Infrastructure Affected by CVE-2026-54576?

EchelonGraph automatically scans your cloud infrastructure and maps CVE exposure using blast radius analysis.

Start Free Scan →Browse All CVEs