CVE-2026-86540

HIGHPre-NVD 7.87.8
EchelonGraph scoreMEDIUM confidence

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

Score 7.8 from GitHub Security Advisory (severity: HIGH) published 2026-10-06. The CNA's CVSS baseline 7.8; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: the CNA's CVSS, EPSS, GitHub Security Advisory
Elevated

Also known asEUVD-2026-72558 (ENISA EUVD) · GHSA-6ph4-r249-58p2 (GitHub Security Advisories) · GHSA-mc52-mwq4-vfx3 (GitHub Security Advisories)Source: ENISA EUVD

7.8EG
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).
  • CISA's Vulnrichment rates exploitation as PoC; EchelonGraph holds no exploit-code reference for it
CISA-KEV: Not listedEPSS PROB: 0.2%CVSS: 7.8Exploit: No code on recordExposed services: Not assessed

A fix is available — apply it.

knowns versions before 0.30.0 fail to validate the settings.lsp.languages binary field in project configuration files, allowing attackers to execute arbitrary binaries by crafting a malicious .knowns/config.json file. When a repository with a crafted configuration is opened, the unvalidated binary path is executed twice under the user's account without any verification.

CVSS v3
7.8
EG Score
7.8HIGHmedium confidence
EG Risk
51
EG Risk 51/100

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)
Severity78% × 45%
Impact severity (EG Severity): CVSS 7.8 of 10. Never the KEV-floored or EPSS-lifted EG Score.
Exploitation40% × 40%
EchelonGraph's fixed weight for EG-KEV Tier 3 (Elevated): a constant, not a probability.
Automatability0% × 15%
CISA's SSVC Automatable value: no (Vulnrichment).
SSVC (CISA's decision table, applied by EchelonGraph): Track at low, Track* at medium and Attend at high mission impact.
Exploitation public PoC (CISA Vulnrichment) · Automatable no (CISA Vulnrichment) · Technical impact total (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
0.2%
EPSS %ILE
11th
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 (7.8): severity, escalated by confirmed exploitation. This CVE's 7.8 is its impact severity (EG Severity), not escalated.

EG Severity
7.8 HIGHCVSS-B, impact only: no KEV listing, EPSS or EG-KEV tier raises it.GitHub Security Advisory CVSS
EG Likelihood
0.2% within 30 daysSource: FIRST EPSS (model v2026.06.15, score date 2026-11-12). 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, Track* at medium and Attend at high mission impact.CISA BOD 26-04: 14 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 low, Track* at medium and Attend at high mission impact.

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

Exploitation public PoC (CISA Vulnrichment) · Automatable no (CISA Vulnrichment) · Technical impact total (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; 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 total (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 7, 2026
Patch available. Sources: github, github_commit, github_release.
Web page

knowns before 0.30.0 Arbitrary Code Execution via LSP Binary | Advisories | VulnCheck

https://www.vulncheck.com/advisories/knowns-before-0.30.0-arbitrary-code-execution-via-lsp-binary
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/models/config.go at v0.29.1 · knowns-dev/knowns · GitHub

https://github.com/knowns-dev/knowns/blob/v0.29.1/internal/models/config.go#L205-L216
Web page

knowns/internal/lsp/detect.go at v0.29.1 · knowns-dev/knowns · GitHub

https://github.com/knowns-dev/knowns/blob/v0.29.1/internal/lsp/detect.go#L128-L157
GitHub advisoryMentions a patch (unverified)

OS Command Injection via Insecure LSP Binary Path Config in .knowns/config.json · Advisory · knowns-dev/knowns · GitHub

https://github.com/knowns-dev/knowns/security/advisories/GHSA-mc52-mwq4-vfx3

Vendor Advisories for CVE-2026-86540(1)

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

Patch Availability(1)

Vendor / EcosystemFix (by version range) / PatchReleasedSource
npmknowns @ 0.30.0 (fixes <= 0.29.1)—ghsa

Patches are aggregated from vendor advisories (Red Hat, Microsoft, Cisco, GitHub) and package ecosystems (OSV, GHSA). Multiple rows for the same upstream release have been deduplicated.

Affected Packages

(1 across 1 ecosystem)
npm(1)
PackageVulnerable rangeFix by version rangeDependents
knowns—
  • every version up to 0.30.0: fixed in 0.30.0
—

Weakness Classification(4)

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

Data Freshness Timeline

(refreshed 7× in last 7d / 32× 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 its CVE.org record (CNA or CISA ADP). 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). "EchelonGraph re-scored" is our own recompute of this CVE's score, not an update from a source, and is not counted in the refreshes above. Most recent first.

Showing the most recent 100 of 171 rows 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 71 oldest rows on record are not shown and were not checked, so the counts can still include repeats.

  1. 2026-11-12 19:57 UTCEchelonGraph re-scored
  2. 2026-11-12 19:57 UTCGHSA enrichmentGHSA-mc52-mwq4-vfx3 · GitHub severity HIGH · GitHub CVSS 7.8
  3. 2026-11-11 16:41 UTCEPSS rescoreEPSS 0.2% · 11th percentile
  4. 2026-11-10 16:45 UTCEPSS rescoreEPSS 0.2% · 11th percentile
  5. 2026-11-09 16:36 UTCEPSS rescoreEPSS 0.2% · 11th percentile
  6. 2026-11-08 16:41 UTCEPSS rescoreEPSS 0.2% · 11th percentile
  7. 2026-11-07 16:40 UTCEPSS rescoreEPSS 0.2% · 11th percentile
  8. 2026-11-06 16:39 UTCEPSS rescoreEPSS 0.2% · 11th percentile
  9. 2026-11-05 19:00 UTCEchelonGraph re-scored
  10. 2026-11-05 19:00 UTCGHSA enrichmentGHSA-mc52-mwq4-vfx3 · GitHub severity HIGH · GitHub CVSS 7.8
  11. 2026-11-05 16:38 UTCEPSS rescoreEPSS 0.2% · 11th percentile
  12. 2026-11-04 16:37 UTCEPSS rescoreEPSS 0.2% · 11th percentile
  13. 2026-11-03 22:02 UTCEchelonGraph re-scored
  14. 2026-11-03 22:02 UTCGHSA enrichmentGHSA-mc52-mwq4-vfx3 · GitHub severity HIGH · GitHub CVSS 7.8
  15. 2026-11-03 16:49 UTCEPSS rescoreEPSS 0.2% · 11th percentile
  16. 2026-11-02 16:46 UTCEPSS rescoreEPSS 0.2% · 11th percentile
  17. 2026-11-01 16:35 UTCEPSS rescoreEPSS 0.2% · 11th percentile
  18. 2026-11-01 07:38 UTCGHSA enrichmentGHSA-mc52-mwq4-vfx3 · GitHub severity HIGH · GitHub CVSS 7.8
  19. 2026-11-01 07:38 UTCEchelonGraph re-scored
  20. 2026-10-31 16:33 UTCEPSS rescoreEPSS 0.2% · 11th percentile
  21. 2026-10-30 16:35 UTCEPSS rescoreEPSS 0.2% · 11th percentile
  22. 2026-10-29 16:34 UTCEPSS rescoreEPSS 0.2% · 11th percentile
  23. 2026-10-28 16:33 UTCEPSS rescoreEPSS 0.2% · 11th percentile
  24. 2026-10-27 20:02 UTCEchelonGraph re-scored
  25. 2026-10-27 16:32 UTCEPSS rescoreEPSS 0.2% · 11th percentile
Show 75 more
  1. 2026-10-26 16:32 UTCEPSS rescoreEPSS 0.2% · 11th percentile
  2. 2026-10-25 16:34 UTCEPSS rescoreEPSS 0.2% · 11th percentile
  3. 2026-10-25 13:54 UTCEchelonGraph re-scored
  4. 2026-10-24 16:34 UTCEPSS rescoreEPSS 0.2% · 10th percentile
  5. 2026-10-23 16:32 UTCEPSS rescoreEPSS 0.2% · 10th percentile
  6. 2026-10-22 16:35 UTCEPSS rescoreEPSS 0.2% · 10th percentile
  7. 2026-10-21 16:34 UTCEPSS rescoreEPSS 0.2% · 10th percentile
  8. 2026-10-20 16:33 UTCEPSS rescoreEPSS 0.2% · 10th percentile
  9. 2026-10-20 07:26 UTCEchelonGraph re-scored
  10. 2026-10-19 16:33 UTCEPSS rescoreEPSS 0.2% · 10th percentile
  11. 2026-10-18 03:04 UTCEchelonGraph re-scored
  12. 2026-10-17 16:35 UTCEPSS rescoreEPSS 0.2% · 10th percentile
  13. 2026-10-16 16:44 UTCEPSS rescoreEPSS 0.2% · 10th percentile
  14. 2026-10-15 16:33 UTCEPSS rescoreEPSS 0.2% · 10th percentile
  15. 2026-10-14 16:34 UTCEPSS rescoreEPSS 0.2% · 10th percentile
  16. 2026-10-13 16:35 UTCEPSS rescoreEPSS 0.2% · 10th percentile
  17. 2026-10-13 05:18 UTCEchelonGraph re-scored
  18. 2026-10-12 16:35 UTCEPSS rescoreEPSS 0.2% · 10th percentile
  19. 2026-10-12 14:51 UTCEchelonGraph re-scored
  20. 2026-10-11 19:17 UTCEchelonGraph re-scored
  21. 2026-10-11 16:33 UTCEchelonGraph re-scored
  22. 2026-10-11 13:50 UTCEchelonGraph re-scored
  23. 2026-10-11 13:49 UTCEPSS rescoreEPSS 0.2% · 10th percentile
  24. 2026-10-10 20:00 UTCEPSS rescoreEPSS 0.2% · 10th percentile
  25. 2026-10-09 22:41 UTCEchelonGraph re-scored
  26. 2026-10-09 20:07 UTCEPSS rescoreEPSS 0.2% · 10th percentile
  27. 2026-10-09 00:49 UTCEchelonGraph re-scored
  28. 2026-10-08 17:13 UTCEPSS rescoreEPSS 0.2% · 10th percentile
  29. 2026-10-08 09:56 UTCEchelonGraph re-scored
  30. 2026-10-07 23:48 UTCEPSS rescoreEPSS 0.2% · 10th percentile
  31. 2026-10-06 22:16 UTCEchelonGraph re-scored
  32. 2026-10-06 15:18 UTCEPSS rescoreEPSS 0.2% · 10th percentile
  33. 2026-10-06 10:53 UTCGHSA enrichmentGHSA-6ph4-r249-58p2 · GitHub severity HIGH · GitHub CVSS 7.8
  34. 2026-10-05 22:54 UTCEchelonGraph re-scored
  35. 2026-10-05 22:54 UTCGHSA enrichmentGHSA-6ph4-r249-58p2 · GitHub severity HIGH · GitHub CVSS 7.8
  36. 2026-10-05 17:44 UTCEPSS rescoreEPSS 0.2% · 10th percentile
  37. 2026-10-05 11:12 UTCGHSA enrichmentGHSA-6ph4-r249-58p2 · GitHub severity HIGH · GitHub CVSS 7.8
  38. 2026-10-04 23:34 UTCEchelonGraph re-scored
  39. 2026-10-04 23:34 UTCGHSA enrichmentGHSA-6ph4-r249-58p2 · GitHub severity HIGH · GitHub CVSS 7.8
  40. 2026-10-04 23:22 UTCEPSS rescoreEPSS 0.2% · 10th percentile
  41. 2026-10-04 12:12 UTCGHSA enrichmentGHSA-6ph4-r249-58p2 · GitHub severity HIGH · GitHub CVSS 7.8
  42. 2026-10-04 00:51 UTCEchelonGraph re-scored
  43. 2026-10-04 00:51 UTCGHSA enrichmentGHSA-6ph4-r249-58p2 · GitHub severity HIGH · GitHub CVSS 7.8
  44. 2026-10-03 12:22 UTCGHSA enrichmentGHSA-6ph4-r249-58p2 · GitHub severity HIGH · GitHub CVSS 7.8
  45. 2026-10-03 00:21 UTCEchelonGraph re-scored
  46. 2026-10-03 00:21 UTCGHSA enrichmentGHSA-6ph4-r249-58p2 · GitHub severity HIGH · GitHub CVSS 7.8
  47. 2026-10-02 12:47 UTCGHSA enrichmentGHSA-6ph4-r249-58p2 · GitHub severity HIGH · GitHub CVSS 7.8
  48. 2026-10-02 01:19 UTCEchelonGraph re-scored
  49. 2026-10-02 01:19 UTCGHSA enrichmentGHSA-6ph4-r249-58p2 · GitHub severity HIGH · GitHub CVSS 7.8
  50. 2026-10-01 19:50 UTCEPSS rescoreEPSS 0.2% · 10th percentile
  51. 2026-10-01 13:58 UTCGHSA enrichmentGHSA-6ph4-r249-58p2 · GitHub severity HIGH · GitHub CVSS 7.8
  52. 2026-10-01 02:37 UTCGHSA enrichmentGHSA-6ph4-r249-58p2 · GitHub severity HIGH · GitHub CVSS 7.8
  53. 2026-09-30 15:16 UTCEchelonGraph re-scored
  54. 2026-09-30 15:16 UTCGHSA enrichmentGHSA-6ph4-r249-58p2 · GitHub severity HIGH · GitHub CVSS 7.8
  55. 2026-09-30 15:04 UTCEPSS rescoreEPSS 0.2% · 10th percentile
  56. 2026-09-30 02:27 UTCEchelonGraph re-scored
  57. 2026-09-30 02:27 UTCGHSA enrichmentGHSA-6ph4-r249-58p2 · GitHub severity HIGH · GitHub CVSS 7.8
  58. 2026-09-29 09:43 UTCGHSA enrichmentGHSA-6ph4-r249-58p2 · GitHub severity HIGH · GitHub CVSS 7.8
  59. 2026-09-28 22:18 UTCEchelonGraph re-scored
  60. 2026-09-28 22:18 UTCGHSA enrichmentGHSA-6ph4-r249-58p2 · GitHub severity HIGH · GitHub CVSS 7.8
  61. 2026-09-28 13:52 UTCEPSS rescoreEPSS 0.2% · 10th percentile
  62. 2026-09-28 10:44 UTCGHSA enrichmentGHSA-6ph4-r249-58p2 · GitHub severity HIGH · GitHub CVSS 7.8
  63. 2026-09-27 23:14 UTCEchelonGraph re-scored
  64. 2026-09-27 23:14 UTCGHSA enrichmentGHSA-6ph4-r249-58p2 · GitHub severity HIGH · GitHub CVSS 7.8
  65. 2026-09-27 13:48 UTCEPSS rescoreEPSS 0.2% · 10th percentile
  66. 2026-09-27 11:52 UTCGHSA enrichmentGHSA-6ph4-r249-58p2 · GitHub severity HIGH · GitHub CVSS 7.8
  67. 2026-09-27 00:31 UTCEchelonGraph re-scored
  68. 2026-09-27 00:31 UTCGHSA enrichmentGHSA-6ph4-r249-58p2 · GitHub severity HIGH · GitHub CVSS 7.8
  69. 2026-09-26 15:59 UTCEPSS rescoreEPSS 0.2% · 10th percentile
  70. 2026-09-26 12:57 UTCGHSA enrichmentGHSA-6ph4-r249-58p2 · GitHub severity HIGH · GitHub CVSS 7.8
  71. 2026-09-26 01:36 UTCEchelonGraph re-scored
  72. 2026-09-26 01:36 UTCGHSA enrichmentGHSA-6ph4-r249-58p2 · GitHub severity HIGH · GitHub CVSS 7.8
  73. 2026-09-25 13:39 UTCGHSA enrichmentGHSA-6ph4-r249-58p2 · GitHub severity HIGH · GitHub CVSS 7.8
  74. 2026-09-25 02:15 UTCGHSA enrichmentGHSA-6ph4-r249-58p2 · GitHub severity HIGH · GitHub CVSS 7.8
  75. 2026-09-24 14:53 UTCEchelonGraph re-scored

Frequently asked(5)

What is CVE-2026-86540?
CVE-2026-86540 is a high-severity vulnerability; its CVE record was published on September 7, 2026. knowns versions before 0.30.0 fail to validate the settings.lsp.languages binary field in project configuration files, allowing attackers to execute arbitrary binaries by crafting a malicious .knowns/config.json file. When a repository with a crafted configuration is opened, the unvalidated binary…
When was CVE-2026-86540 made public?
CVE-2026-86540 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-2026-86540 actively exploited?
CVE-2026-86540 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0.2% probability of exploitation in the next 30 days (11th percentile of EPSS-scored CVEs).
What is the CVSS score of CVE-2026-86540?
CVE-2026-86540 has a CVSS base score of 7.8 (the CNA's own assessment, by vulncheck; NVD's own analysis pending).
How do I remediate CVE-2026-86540?
A fix for CVE-2026-86540 is available: update to the fixed version the vendor names in its advisory. The vendor advisories EchelonGraph has for CVE-2026-86540 are linked in the Vendor Advisories panel on this page.

Dependency Blast Radius

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