CVE-2026-86542

CRITICALPre-NVD 9.19.1
EchelonGraph scoreMEDIUM confidence

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

Score 9.1 from GitHub Security Advisory (severity: HIGH) published 2026-09-08. The CNA's CVSS baseline 9.1; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: the CNA's CVSS, EPSS, GitHub Security Advisory
Trending — 3 sources updated this week

Also known asEUVD-2026-72560 (ENISA EUVD) · GHSA-8mhw-737q-f96r (GitHub Security Advisories)Source: ENISA EUVD

9.1EG
EchelonGraph verdictPlan a fixRemediate within your standard update timelines at low or medium mission impact and sooner than that at high (the SSVC decision on this page).
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS PROB: 0.7%CVSS: 9.1Exploit: None knownExposed services: Not assessed

A fix is available — apply it.

knowns before 0.30.0 fails to validate import names in the import routes, allowing unauthenticated attackers to write files outside the imports directory. Attackers can supply traversal sequences in the name parameter to escape the imports directory and overwrite arbitrary files writable by the server process.

CVSS v3
9.1
EG Score
9.1CRITICALmedium confidence
EG Risk
56
EG Risk 56/100

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)
Severity91% × 45%
Impact severity (EG Severity): CVSS 9.1 of 10. Never the KEV-floored or EPSS-lifted EG Score.
Exploitation0.7% × 40%
FIRST EPSS: the 30-day exploitation probability when EchelonGraph scored this CVE.
Automatability100% × 15%
CISA's SSVC Automatable value: yes (Vulnrichment).
SSVC (CISA's decision table, applied by EchelonGraph): Track at low or medium mission impact; Attend at high (mission-essential systems).
Exploitation none (CISA Vulnrichment) · Automatable yes (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 at low or medium mission impact and sooner than that at high.
EPSS PROB
0.7%
EPSS %ILE
54th
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 (9.1): severity, escalated by confirmed exploitation. This CVE's 9.1 is its impact severity (EG Severity), not escalated.

EG Severity
9.1 CRITICALCVSS-B, impact only: no KEV listing, EPSS or EG-KEV tier raises it.GitHub Security Advisory CVSS
EG Likelihood
0.7% within 30 daysSource: FIRST EPSS (model v2026.06.15, score date 2026-11-01). 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 low or medium mission impact; Attend at high (mission-essential systems).CISA BOD 26-04: 14 days if the affected system is publicly exposed; 60 days 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 low or medium mission impact; Attend at high (mission-essential systems).

A fix is available. Apply it within your standard update timelines at low or medium mission impact and sooner than that at high.

Exploitation none (CISA Vulnrichment) · Automatable yes (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)14 days if the affected system is publicly exposed; 60 days if it is not.

The score's inputs: In CISA KEV no (CISA's KEV catalog) · Automatable yes (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 7, 2026

Last Modified

September 24, 2026

Advisory Details (6)

Auto-updated Sep 15, 2026
Patch available. Sources: github_commit, github_release, github.
Web page

knowns before 0.30.0 Path Traversal via Import Name | Advisories | VulnCheck

https://www.vulncheck.com/advisories/knowns-before-0.30.0-path-traversal-via-import-name
GitHub release Patch Available

v0.30.0

Patch available: knowns-dev/knowns v0.30.0

https://github.com/knowns-dev/knowns/releases/tag/v0.30.0
GitHub commit

commit d3989829fb50 (knowns-dev/knowns)

Fix landed in knowns-dev/knowns commit d3989829fb50 — awaiting tagged release

https://github.com/knowns-dev/knowns/commit/d3989829fb5095666d23d005b2f78a082832a396
Web page

knowns/internal/server/routes/imports.go at v0.29.1 · knowns-dev/knowns · GitHub

https://github.com/knowns-dev/knowns/blob/v0.29.1/internal/server/routes/imports.go#L376-L420
Web page

knowns/internal/server/routes/imports.go at v0.29.1 · knowns-dev/knowns · GitHub

https://github.com/knowns-dev/knowns/blob/v0.29.1/internal/server/routes/imports.go#L519-L551
GitHub advisoryMentions a patch (unverified)

Unauthenticated Remote Code Execution via REST API Path Traversal + LSP Binary Override · Advisory · knowns-dev/knowns · GitHub

https://github.com/knowns-dev/knowns/security/advisories/GHSA-wh3c-v55g-qfg8

Vendor Advisories for CVE-2026-86542(1)

These vendors published their own advisory mentioning this CVE — often with vendor-specific remediation steps + affected product lists not in NVD.

Weakness Classification(1)

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

Data Freshness Timeline

(refreshed 22× in last 7d / 122× 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.

Showing the most recent 100 of 335 refreshes on record for this CVE.

A repeat, a row identical to one the same pipeline wrote less than 10 seconds earlier, is not a separate refresh and is not counted. None are among the latest 100 rows. The 235 oldest rows on record are not shown and were not checked, so the counts can still include repeats.

  1. 2026-11-02 16:46 UTCEPSS rescoreEPSS 0.7% · 54th percentile
  2. 2026-11-02 15:36 UTCGHSA enrichmentGHSA-8mhw-737q-f96r · GitHub severity HIGH · GitHub CVSS 9.1
  3. 2026-11-01 17:00 UTCEG score recompute
  4. 2026-11-01 17:00 UTCGHSA enrichmentGHSA-8mhw-737q-f96r · GitHub severity HIGH · GitHub CVSS 9.1
  5. 2026-11-01 16:35 UTCEPSS rescoreEPSS 0.7% · 54th percentile
  6. 2026-10-31 18:26 UTCEG score recompute
  7. 2026-10-31 18:26 UTCGHSA enrichmentGHSA-8mhw-737q-f96r · GitHub severity HIGH · GitHub CVSS 9.1
  8. 2026-10-31 16:33 UTCEPSS rescoreEPSS 0.7% · 54th percentile
  9. 2026-10-30 19:36 UTCEG score recompute
  10. 2026-10-30 19:36 UTCGHSA enrichmentGHSA-8mhw-737q-f96r · GitHub severity HIGH · GitHub CVSS 9.1
  11. 2026-10-30 16:35 UTCEPSS rescoreEPSS 0.7% · 54th percentile
  12. 2026-10-29 20:46 UTCEG score recompute
  13. 2026-10-29 20:46 UTCGHSA enrichmentGHSA-8mhw-737q-f96r · GitHub severity HIGH · GitHub CVSS 9.1
  14. 2026-10-29 16:34 UTCEPSS rescoreEPSS 0.7% · 54th percentile
  15. 2026-10-28 22:11 UTCEG score recompute
  16. 2026-10-28 22:11 UTCGHSA enrichmentGHSA-8mhw-737q-f96r · GitHub severity HIGH · GitHub CVSS 9.1
  17. 2026-10-28 16:33 UTCEPSS rescoreEPSS 0.7% · 54th percentile
  18. 2026-10-27 23:34 UTCEG score recompute
  19. 2026-10-27 23:34 UTCGHSA enrichmentGHSA-8mhw-737q-f96r · GitHub severity HIGH · GitHub CVSS 9.1
  20. 2026-10-27 16:32 UTCEPSS rescoreEPSS 0.7% · 54th percentile
  21. 2026-10-27 00:55 UTCEG score recompute
  22. 2026-10-27 00:55 UTCGHSA enrichmentGHSA-8mhw-737q-f96r · GitHub severity HIGH · GitHub CVSS 9.1
  23. 2026-10-26 16:32 UTCEPSS rescoreEPSS 0.7% · 54th percentile
  24. 2026-10-25 22:36 UTCEG score recompute
  25. 2026-10-25 22:36 UTCGHSA enrichmentGHSA-8mhw-737q-f96r · GitHub severity HIGH · GitHub CVSS 9.1
Show 75 more
  1. 2026-10-25 16:34 UTCEPSS rescoreEPSS 0.7% · 54th percentile
  2. 2026-10-25 13:54 UTCEG score recompute
  3. 2026-10-25 00:00 UTCEG score recompute
  4. 2026-10-25 00:00 UTCGHSA enrichmentGHSA-8mhw-737q-f96r · GitHub severity HIGH · GitHub CVSS 9.1
  5. 2026-10-24 16:34 UTCEPSS rescoreEPSS 0.7% · 54th percentile
  6. 2026-10-24 01:25 UTCEG score recompute
  7. 2026-10-24 01:25 UTCGHSA enrichmentGHSA-8mhw-737q-f96r · GitHub severity HIGH · GitHub CVSS 9.1
  8. 2026-10-23 16:32 UTCEPSS rescoreEPSS 0.7% · 54th percentile
  9. 2026-10-23 02:49 UTCEG score recompute
  10. 2026-10-23 02:49 UTCGHSA enrichmentGHSA-8mhw-737q-f96r · GitHub severity HIGH · GitHub CVSS 9.1
  11. 2026-10-22 16:35 UTCEPSS rescoreEPSS 0.7% · 54th percentile
  12. 2026-10-22 04:14 UTCEG score recompute
  13. 2026-10-22 04:14 UTCGHSA enrichmentGHSA-8mhw-737q-f96r · GitHub severity HIGH · GitHub CVSS 9.1
  14. 2026-10-21 16:34 UTCEPSS rescoreEPSS 0.7% · 54th percentile
  15. 2026-10-21 05:28 UTCEG score recompute
  16. 2026-10-21 05:28 UTCGHSA enrichmentGHSA-8mhw-737q-f96r · GitHub severity HIGH · GitHub CVSS 9.1
  17. 2026-10-20 16:33 UTCEPSS rescoreEPSS 0.7% · 53rd percentile
  18. 2026-10-20 06:52 UTCEG score recompute
  19. 2026-10-20 06:52 UTCGHSA enrichmentGHSA-8mhw-737q-f96r · GitHub severity HIGH · GitHub CVSS 9.1
  20. 2026-10-19 16:33 UTCEPSS rescoreEPSS 0.7% · 53rd percentile
  21. 2026-10-19 08:14 UTCEG score recompute
  22. 2026-10-19 08:14 UTCGHSA enrichmentGHSA-8mhw-737q-f96r · GitHub severity HIGH · GitHub CVSS 9.1
  23. 2026-10-18 09:29 UTCGHSA enrichmentGHSA-8mhw-737q-f96r · GitHub severity HIGH · GitHub CVSS 9.1
  24. 2026-10-18 03:04 UTCEG score recompute
  25. 2026-10-17 16:35 UTCEPSS rescoreEPSS 0.7% · 53rd percentile
  26. 2026-10-17 10:53 UTCEG score recompute
  27. 2026-10-17 10:53 UTCGHSA enrichmentGHSA-8mhw-737q-f96r · GitHub severity HIGH · GitHub CVSS 9.1
  28. 2026-10-16 16:44 UTCEPSS rescoreEPSS 0.7% · 53rd percentile
  29. 2026-10-16 12:15 UTCEG score recompute
  30. 2026-10-16 12:15 UTCGHSA enrichmentGHSA-8mhw-737q-f96r · GitHub severity HIGH · GitHub CVSS 9.1
  31. 2026-10-15 16:33 UTCEPSS rescoreEPSS 0.7% · 53rd percentile
  32. 2026-10-15 13:36 UTCEG score recompute
  33. 2026-10-15 13:36 UTCGHSA enrichmentGHSA-8mhw-737q-f96r · GitHub severity HIGH · GitHub CVSS 9.1
  34. 2026-10-14 16:34 UTCEPSS rescoreEPSS 0.7% · 53rd percentile
  35. 2026-10-14 08:35 UTCEG score recompute
  36. 2026-10-14 08:35 UTCGHSA enrichmentGHSA-8mhw-737q-f96r · GitHub severity HIGH · GitHub CVSS 9.1
  37. 2026-10-13 16:35 UTCEPSS rescoreEPSS 0.7% · 53rd percentile
  38. 2026-10-13 03:48 UTCEG score recompute
  39. 2026-10-13 03:48 UTCGHSA enrichmentGHSA-8mhw-737q-f96r · GitHub severity HIGH · GitHub CVSS 9.1
  40. 2026-10-12 16:35 UTCEPSS rescoreEPSS 0.7% · 53rd percentile
  41. 2026-10-12 14:51 UTCEG score recompute
  42. 2026-10-12 05:12 UTCGHSA enrichmentGHSA-8mhw-737q-f96r · GitHub severity HIGH · GitHub CVSS 9.1
  43. 2026-10-11 19:17 UTCEG score recompute
  44. 2026-10-11 16:33 UTCEG score recompute
  45. 2026-10-11 13:50 UTCEG score recompute
  46. 2026-10-11 13:49 UTCEPSS rescoreEPSS 0.7% · 53rd percentile
  47. 2026-10-10 20:00 UTCEPSS rescoreEPSS 0.7% · 53rd percentile
  48. 2026-10-10 17:17 UTCGHSA enrichmentGHSA-8mhw-737q-f96r · GitHub severity HIGH · GitHub CVSS 9.1
  49. 2026-10-10 13:34 UTCGHSA enrichmentGHSA-8mhw-737q-f96r · GitHub severity HIGH · GitHub CVSS 9.1
  50. 2026-10-10 09:56 UTCGHSA enrichmentGHSA-8mhw-737q-f96r · GitHub severity HIGH · GitHub CVSS 9.1
  51. 2026-10-10 06:18 UTCGHSA enrichmentGHSA-8mhw-737q-f96r · GitHub severity HIGH · GitHub CVSS 9.1
  52. 2026-10-10 02:31 UTCGHSA enrichmentGHSA-8mhw-737q-f96r · GitHub severity HIGH · GitHub CVSS 9.1
  53. 2026-10-09 22:41 UTCEG score recompute
  54. 2026-10-09 22:40 UTCGHSA enrichmentGHSA-8mhw-737q-f96r · GitHub severity HIGH · GitHub CVSS 9.1
  55. 2026-10-09 20:07 UTCEPSS rescoreEPSS 0.7% · 53rd percentile
  56. 2026-10-09 08:09 UTCGHSA enrichmentGHSA-8mhw-737q-f96r · GitHub severity HIGH · GitHub CVSS 9.1
  57. 2026-10-09 04:29 UTCGHSA enrichmentGHSA-8mhw-737q-f96r · GitHub severity HIGH · GitHub CVSS 9.1
  58. 2026-10-09 00:49 UTCEG score recompute
  59. 2026-10-09 00:48 UTCGHSA enrichmentGHSA-8mhw-737q-f96r · GitHub severity HIGH · GitHub CVSS 9.1
  60. 2026-10-08 17:13 UTCEPSS rescoreEPSS 0.7% · 53rd percentile
  61. 2026-10-08 09:28 UTCGHSA enrichmentGHSA-8mhw-737q-f96r · GitHub severity HIGH · GitHub CVSS 9.1
  62. 2026-10-08 05:49 UTCGHSA enrichmentGHSA-8mhw-737q-f96r · GitHub severity HIGH · GitHub CVSS 9.1
  63. 2026-10-08 02:12 UTCEG score recompute
  64. 2026-10-08 02:12 UTCGHSA enrichmentGHSA-8mhw-737q-f96r · GitHub severity HIGH · GitHub CVSS 9.1
  65. 2026-10-07 23:48 UTCEPSS rescoreEPSS 0.7% · 53rd percentile
  66. 2026-10-07 22:34 UTCGHSA enrichmentGHSA-8mhw-737q-f96r · GitHub severity HIGH · GitHub CVSS 9.1
  67. 2026-10-07 15:22 UTCGHSA enrichmentGHSA-8mhw-737q-f96r · GitHub severity HIGH · GitHub CVSS 9.1
  68. 2026-10-07 10:09 UTCGHSA enrichmentGHSA-8mhw-737q-f96r · GitHub severity HIGH · GitHub CVSS 9.1
  69. 2026-10-07 06:32 UTCGHSA enrichmentGHSA-8mhw-737q-f96r · GitHub severity HIGH · GitHub CVSS 9.1
  70. 2026-10-07 02:54 UTCGHSA enrichmentGHSA-8mhw-737q-f96r · GitHub severity HIGH · GitHub CVSS 9.1
  71. 2026-10-06 23:16 UTCGHSA enrichmentGHSA-8mhw-737q-f96r · GitHub severity HIGH · GitHub CVSS 9.1
  72. 2026-10-06 19:40 UTCGHSA enrichmentGHSA-8mhw-737q-f96r · GitHub severity HIGH · GitHub CVSS 9.1
  73. 2026-10-06 16:00 UTCEG score recompute
  74. 2026-10-06 16:00 UTCGHSA enrichmentGHSA-8mhw-737q-f96r · GitHub severity HIGH · GitHub CVSS 9.1
  75. 2026-10-06 15:18 UTCEPSS rescoreEPSS 0.7% · 53rd percentile

Frequently asked(5)

What is CVE-2026-86542?
CVE-2026-86542 is a critical-severity vulnerability; its CVE record was published on September 7, 2026. knowns before 0.30.0 fails to validate import names in the import routes, allowing unauthenticated attackers to write files outside the imports directory. Attackers can supply traversal sequences in the name parameter to escape the imports directory and overwrite arbitrary files writable by the…
When was CVE-2026-86542 made public?
CVE-2026-86542 was made public on August 16, 2026: that is the date its CVE record's CNA, VulnCheck, gives for when the vulnerability was made public. The CVE record itself was published on September 7, 2026. EchelonGraph's copy of the record carries a last-modified date of September 24, 2026; the record at its source may have been updated since.
Is CVE-2026-86542 actively exploited?
CVE-2026-86542 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0.7% probability of exploitation in the next 30 days (54th percentile of EPSS-scored CVEs).
What is the CVSS score of CVE-2026-86542?
CVE-2026-86542 has a CVSS base score of 9.1 (the CNA's own assessment, by vulncheck; NVD's own analysis pending).
How do I remediate CVE-2026-86542?
A fix for CVE-2026-86542 is available: update to the fixed version the vendor names in its advisory. The vendor advisories EchelonGraph has for CVE-2026-86542 are linked in the Vendor Advisories panel on this page.

Dependency Blast Radius

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