CVE-2026-54587

MEDIUMPre-NVD 5.85.8
EchelonGraph scoreMEDIUM confidence

“—” beside the score: it is equal to the CVSS score beside it.

This medium-severity CVE scores 5.8 under a secondary CVSS source (NVD's own analysis pending). EPSS exploit probability: 0.1% (1st percentile of EPSS-scored CVEs). No GitHub Security Advisory CVSS is on record for this CVE.

Triggered by: Headline CVSS from a secondary CVSS source
Sources: EPSS, a secondary CVSS source

Also known asEUVD-2026-82328 (ENISA EUVD)Source: ENISA EUVD

5.8EG
EchelonGraph verdictMonitorRemediate within your standard update timelines (the SSVC decision on this page).
  • Lower severity and no public exploit yet
CISA-KEV: Not listedEPSS PROB: 0.1%CVSS: 5.8Exploit: None knownExposed services: Not assessed

A fix is available — apply it.

mport is the MidnightBSD Package Manager. Prior to 2.7.8, directory assets handled as ASSET_DIR or ASSET_DIR_OWNER_MODE in libmport/bundle_read_install_pkg.c used path-based mport_mkdirp(), ownership, and permission operations. A local attacker able to modify part of the target installation tree could use dot-dot traversal or substitute symlinks during privileged package installation, causing directory creation or attribute changes to affect attacker-selected paths outside the intended package directories. This issue is fixed in version 2.7.8.

CVSS v3
5.8
EG Score
5.8MEDIUMmedium confidence
EG Risk
26
EG Risk 26/100

EG Risk is EchelonGraph's 0–100 priority score. It fuses impact severity (EG Severity, the CVSS base score, never the KEV-floored or EPSS-lifted EG Score) with real-world exploitation and automatability, under weights EchelonGraph set by hand, so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner.

How it’s computed (value × EchelonGraph’s weight)
Severity58% × 45%
Impact severity (EG Severity): CVSS 5.8 of 10. Never the KEV-floored or EPSS-lifted EG Score.
Exploitation0.1% × 40%
FIRST EPSS: the 30-day exploitation probability when EchelonGraph scored this CVE.
Automatability0% × 15%
CISA's SSVC Automatable value: no (Vulnrichment).
SSVC (CISA's decision table, applied by EchelonGraph): Track at every mission impact level.
Exploitation none (CISA Vulnrichment) · Automatable no (CISA Vulnrichment) · Technical impact partial (CISA Vulnrichment). All three are CISA's SSVC values (Vulnrichment). EchelonGraph applied CISA's decision table to them; CISA publishes SSVC inputs and the table, not a decision for each CVE.
Action: A fix is available. Apply it within your standard update timelines.
EPSS PROB
0.1%
EPSS %ILE
1st
KEV
Not listed

What the EG score is made of (scorer v4.0: the three questions the 0–10 score mixes, published apart · methodology)

The EG score (5.8): severity, escalated by confirmed exploitation. This CVE's 5.8 is its impact severity (EG Severity), not escalated.

EG Severity
5.8 MEDIUMCVSS-B, impact only: no KEV listing, EPSS or EG-KEV tier raises it.a secondary CVSS source · CVSS v3.0 or v3.1
EG Likelihood
0.1% within 30 daysSource: FIRST EPSS (model v2026.06.15, score date 2026-10-24). FIRST's exploitation probability, not an EchelonGraph model.
Confirmed exploitation
None on record (CISA KEV, EG-KEV Tier 1)Reported apart from the likelihood: an observed fact, not a probability.
EG Priority
SSVC Track at medium mission impactTrack at every mission impact level.CISA BOD 26-04: 60 days if the affected system is publicly exposed; Fix on system upgrade if it is not.Each input and its source, and whom BOD 26-04 binds: the SSVC and BOD 26-04 blocks below.

SSVC (CISA's decision table, applied by EchelonGraph)Track at every mission impact level.

A fix is available. Apply it within your standard update timelines.

Exploitation none (CISA Vulnrichment) · Automatable no (CISA Vulnrichment) · Technical impact partial (CISA Vulnrichment). All three are CISA's SSVC values (Vulnrichment). EchelonGraph applied CISA's decision table to them; CISA publishes SSVC inputs and the table, not a decision for each CVE. Mission impact is CISA's Mission & Well-being decision point, and only you can judge it. CISA's table makes it high when Mission Prevalence is Essential — the vulnerable component "directly provides capabilities that constitute at least one MEF for at least one entity" (MEF: mission essential function) — or when Public Well-Being Impact is Irreversible: "multiple fatalities are likely", the cyber-physical system "is likely lost or destroyed", "extreme or serious externalities" are imposed on other parties, or social systems such as elections or the financial grid "are destabilized and potentially collapse". CISA's decision table

BOD 26-04 (CISA's remediation timeline, Table 1)60 days if the affected system is publicly exposed; Fix on system upgrade if it is not.

The score's inputs: In CISA KEV no (CISA's KEV catalog) · Automatable no (CISA Vulnrichment) · Technical impact partial (CISA Vulnrichment). Whether your system is publicly exposed is yours to answer. BOD 26-04 binds US Federal Civilian Executive Branch agencies; for anyone else it is CISA's published timeline, a reference rather than an obligation. The directive · how EchelonGraph applies it

Published

September 17, 2026

Last Modified

September 17, 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 a4fa996df1fb (MidnightBSD/mport)

Patch available: MidnightBSD/mport 2.7.8 (contains commit a4fa996df1fb)

https://github.com/MidnightBSD/mport/commit/a4fa996df1fbebeff3691e1b512c807b5f414b5d
GitHub pull request Patch Available

Security fix: Dir asset openat

Patch available: MidnightBSD/mport 2.7.8 (PR #119 merged 2026-04-23)

https://github.com/MidnightBSD/mport/pull/119
GitHub advisoryMentions a patch (unverified)

mport directory asset installation is vulnerable to symlink and path traversal races · Advisory · MidnightBSD/mport · GitHub

Affected: 2.7.8

https://github.com/MidnightBSD/mport/security/advisories/GHSA-f69w-h3gh-r86p

Weakness Classification(2)

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

Data Freshness Timeline

(refreshed 5× in last 7d / 33× in last 30d)

Each row is a time one of our pipelines fetched, updated or re-scored this CVE. 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. An arrow marks a change the record states ("CVSS v3 → 9.1"); EPSS and GHSA rows show the values recorded at that time, not what changed (EPSS values are rounded; hover one for the exact figures). Most recent first.

  1. 2026-10-31 16:33 UTCEPSS rescoreEPSS 0.1% · 1st percentile
  2. 2026-10-30 16:34 UTCEPSS rescoreEPSS 0.1% · 1st percentile
  3. 2026-10-30 11:25 UTCOSV refresh
  4. 2026-10-29 16:33 UTCEPSS rescoreEPSS 0.1% · 1st percentile
  5. 2026-10-28 16:32 UTCEPSS rescoreEPSS 0.1% · 1st percentile
  6. 2026-10-25 16:33 UTCEPSS rescoreEPSS 0.1% · 1st percentile
  7. 2026-10-25 14:19 UTCEG score recompute
  8. 2026-10-22 21:20 UTCEG score recompute
  9. 2026-10-21 16:33 UTCEPSS rescoreEPSS 0.1% · 1st percentile
  10. 2026-10-20 16:33 UTCEPSS rescoreEPSS 0.1% · 1st percentile
  11. 2026-10-18 03:30 UTCEG score recompute
  12. 2026-10-17 16:34 UTCEPSS rescoreEPSS 0.1% · below the 1st percentile
  13. 2026-10-16 16:42 UTCEPSS rescoreEPSS 0.1% · below the 1st percentile
  14. 2026-10-15 16:32 UTCEPSS rescoreEPSS 0.1% · below the 1st percentile
  15. 2026-10-14 16:33 UTCEPSS rescoreEPSS 0.1% · below the 1st percentile
  16. 2026-10-13 16:34 UTCEPSS rescoreEPSS 0.1% · below the 1st percentile
  17. 2026-10-12 15:56 UTCEG score recompute
  18. 2026-10-11 19:39 UTCEG score recompute
  19. 2026-10-11 16:54 UTCEG score recompute
  20. 2026-10-11 14:17 UTCEG score recompute
  21. 2026-10-11 13:49 UTCEPSS rescoreEPSS 0.1% · below the 1st percentile
  22. 2026-10-10 20:00 UTCEPSS rescoreEPSS 0.1% · below the 1st percentile
  23. 2026-10-10 14:08 UTCEG score recompute
  24. 2026-10-09 20:07 UTCEPSS rescoreEPSS 0.1% · below the 1st percentile
  25. 2026-10-09 13:27 UTCEG score recompute
Show 36 more
  1. 2026-10-08 17:12 UTCEPSS rescoreEPSS 0.1% · below the 1st percentile
  2. 2026-10-08 12:04 UTCEG score recompute
  3. 2026-10-07 23:48 UTCEPSS rescoreEPSS 0.1% · below the 1st percentile
  4. 2026-10-07 10:50 UTCEG score recompute
  5. 2026-10-06 15:18 UTCEPSS rescoreEPSS 0.1% · below the 1st percentile
  6. 2026-10-05 09:25 UTCEG score recompute
  7. 2026-10-04 23:22 UTCEPSS rescoreEPSS 0.1% · below the 1st percentile
  8. 2026-10-04 08:45 UTCEG score recompute
  9. 2026-10-03 14:26 UTCEPSS rescoreEPSS 0.1% · below the 1st percentile
  10. 2026-10-03 08:04 UTCEG score recompute
  11. 2026-10-02 17:56 UTCEPSS rescoreEPSS 0.1% · below the 1st percentile
  12. 2026-10-02 07:03 UTCEG score recompute
  13. 2026-10-01 19:50 UTCEPSS rescoreEPSS 0.1% · below the 1st percentile
  14. 2026-10-01 06:22 UTCEG score recompute
  15. 2026-09-30 15:03 UTCEPSS rescoreEPSS 0.1% · below the 1st percentile
  16. 2026-09-30 05:42 UTCEG score recompute
  17. 2026-09-29 15:22 UTCEPSS rescoreEPSS 0.1% · below the 1st percentile
  18. 2026-09-29 04:58 UTCEG score recompute
  19. 2026-09-28 04:17 UTCEG score recompute
  20. 2026-09-27 13:48 UTCEPSS rescoreEPSS 0.1% · below the 1st percentile
  21. 2026-09-27 03:37 UTCEG score recompute
  22. 2026-09-26 15:59 UTCEPSS rescoreEPSS 0.1% · below the 1st percentile
  23. 2026-09-26 02:49 UTCEG score recompute
  24. 2026-09-25 02:08 UTCEG score recompute
  25. 2026-09-24 14:04 UTCEPSS rescoreEPSS 0.1% · below the 1st percentile
  26. 2026-09-22 00:04 UTCEG score recompute
  27. 2026-09-20 23:24 UTCEG score recompute
  28. 2026-09-20 20:16 UTCEPSS rescoreEPSS 0.1% · below the 1st percentile
  29. 2026-09-19 22:42 UTCEG score recompute
  30. 2026-09-18 22:01 UTCEG score recompute
  31. 2026-09-18 19:28 UTCEPSS rescoreEPSS 0.1% · below the 1st percentile
  32. 2026-09-17 20:18 UTCEG score recompute
  33. 2026-09-17 19:20 UTCEG score recompute
  34. 2026-09-17 17:35 UTCEG score recompute
  35. 2026-09-17 17:07 UTCEG score recomputeFirst assessed: 5.8 MEDIUM
  36. 2026-09-17 17:04 UTCMITRE cvelistV5first tracked

Frequently asked(5)

What is CVE-2026-54587?
CVE-2026-54587 is a medium-severity vulnerability; its CVE record was published on September 17, 2026. mport is the MidnightBSD Package Manager. Prior to 2.7.8, directory assets handled as ASSET_DIR or ASSET_DIR_OWNER_MODE in libmport/bundle_read_install_pkg.c used path-based mport_mkdirp(), ownership, and permission operations. A local attacker able to modify part of the target installation tree…
When was the CVE record for CVE-2026-54587 published?
The CVE record for CVE-2026-54587 was published on September 17, 2026. That is the record's publication date; the vulnerability itself may have been made public earlier. EchelonGraph's copy of the record carries a last-modified date of September 17, 2026; the record at its source may have been updated since.
Is CVE-2026-54587 actively exploited?
CVE-2026-54587 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0.1% probability of exploitation in the next 30 days (1st percentile of EPSS-scored CVEs).
What is the CVSS score of CVE-2026-54587?
CVE-2026-54587 has a CVSS base score of 5.8 (a secondary CVSS source that NVD displays; NVD's own analysis pending).
How do I remediate CVE-2026-54587?
A fix for CVE-2026-54587 is available: update to the fixed version the vendor names in its advisory.

Dependency Blast Radius

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