CVE-2026-56274

CRITICALPre-NVD 9.99.9
EchelonGraph scoreMEDIUM confidence

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

Score 9.9 from GitHub Security Advisory (severity: HIGH) published 2026-06-23. A secondary CVSS source baseline 9.9; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: EPSS, GitHub Security Advisory, a secondary CVSS source
Trending — 3 sources updated this weekWeaponized

Also known asEUVD-2026-38434 (ENISA EUVD) · GHSA-8rhx-2hcv-q49g (GitHub Security Advisories)Source: ENISA EUVD

9.9EG
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).
  • Public exploit code is available (Metasploit)
CISA-KEV: Not listedEPSS PROB: 7.5%CVSS: 9.9Exploit: MetasploitExposed services: Not assessed

A fix is available — apply it.

Flowise before 3.1.2 contains multiple OS command injection vulnerabilities in the Custom MCP Server feature due to incomplete command-flag validation and a regex bypass in local file access restrictions. An attacker with a Flowise account of any role, or API access with view/update permissions for chatflows, can configure a malicious MCP server to bypass the validateCommandFlags blocklist (for example, 'docker build' is not blocked, and 'npx --yes' is not blocked while only '-y' is) and the validateArgsForLocalFileAccess checks, resulting in execution of arbitrary commands on the Flowise host.

CVSS v3
9.9
EG Score
9.9CRITICALmedium confidence
EG Risk
71
EG Risk 71/100

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)
Severity99% × 45%
Impact severity (EG Severity): CVSS 9.9 of 10. Never the KEV-floored or EPSS-lifted EG Score.
Exploitation65% × 40%
EchelonGraph's fixed weight for EG-KEV Tier 2 (Weaponized): 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
7.5%
EPSS %ILE
94th
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 (9.9): severity, escalated by confirmed exploitation. This CVE's 9.9 is its impact severity (EG Severity), not escalated.

EG Severity
9.9 CRITICALCVSS-B, impact only: no KEV listing, EPSS or EG-KEV tier raises it.GitHub Security Advisory CVSS
EG Likelihood
7.5% 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, 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

June 23, 2026

Last Modified

June 25, 2026

Advisory Details (2)

Auto-updated Nov 2, 2026
Patch available. Sources: github.
GitHub advisoryMentions a patch (unverified)

Flowise MCP Security Bypass Enables RCE · Advisory · FlowiseAI/Flowise · GitHub

https://github.com/FlowiseAI/Flowise/security/advisories/GHSA-m99r-2hxc-cp3q
Web page

Flowise - Remote Code Execution via MCP Security Bypass in validateCommandFlags and validateArgsForLocalFileAccess | Advisories | VulnCheck

https://www.vulncheck.com/advisories/flowise-remote-code-execution-via-mcp-security-bypass-in-validatecommandflags-and-validateargsforlocalfileaccess

Vendor Advisories for CVE-2026-56274(1)

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

Affected Packages

(2 across 1 ecosystem)
npm(2)
PackageVulnerable rangeFix by version rangeDependents
flowise—
  • every version up to 3.1.2: fixed in 3.1.2
—
flowise-components—
  • every version up to 3.1.2: fixed in 3.1.2
—

Weakness Classification(1)

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

Data Freshness Timeline

(refreshed 20× in last 7d / 75× 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 480 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 380 oldest rows on record are not shown and were not checked, so the counts can still include repeats.

  1. 2026-11-02 02:52 UTCEG score recompute
  2. 2026-11-02 02:51 UTCGHSA enrichmentGHSA-8rhx-2hcv-q49g · GitHub severity HIGH · GitHub CVSS 9.9
  3. 2026-11-01 01:53 UTCEG score recompute
  4. 2026-11-01 01:53 UTCGHSA enrichmentGHSA-8rhx-2hcv-q49g · GitHub severity HIGH · GitHub CVSS 9.9
  5. 2026-10-31 16:33 UTCEPSS rescoreEPSS 7.5% · 94th percentile
  6. 2026-10-31 00:55 UTCEG score recompute
  7. 2026-10-31 00:55 UTCGHSA enrichmentGHSA-8rhx-2hcv-q49g · GitHub severity HIGH · GitHub CVSS 9.9
  8. 2026-10-30 16:34 UTCEPSS rescoreEPSS 7.5% · 94th percentile
  9. 2026-10-29 23:57 UTCEG score recompute
  10. 2026-10-29 23:57 UTCGHSA enrichmentGHSA-8rhx-2hcv-q49g · GitHub severity HIGH · GitHub CVSS 9.9
  11. 2026-10-29 16:33 UTCEPSS rescoreEPSS 7.5% · 94th percentile
  12. 2026-10-28 23:00 UTCEG score recompute
  13. 2026-10-28 22:59 UTCGHSA enrichmentGHSA-8rhx-2hcv-q49g · GitHub severity HIGH · GitHub CVSS 9.9
  14. 2026-10-28 16:32 UTCEPSS rescoreEPSS 7.5% · 94th percentile
  15. 2026-10-27 22:02 UTCEG score recompute
  16. 2026-10-27 22:02 UTCGHSA enrichmentGHSA-8rhx-2hcv-q49g · GitHub severity HIGH · GitHub CVSS 9.9
  17. 2026-10-27 16:32 UTCEPSS rescoreEPSS 7.5% · 94th percentile
  18. 2026-10-26 21:04 UTCEG score recompute
  19. 2026-10-26 21:04 UTCGHSA enrichmentGHSA-8rhx-2hcv-q49g · GitHub severity HIGH · GitHub CVSS 9.9
  20. 2026-10-26 16:31 UTCEPSS rescoreEPSS 7.5% · 94th percentile
  21. 2026-10-25 18:02 UTCEG score recompute
  22. 2026-10-25 18:02 UTCGHSA enrichmentGHSA-8rhx-2hcv-q49g · GitHub severity HIGH · GitHub CVSS 9.9
  23. 2026-10-25 16:33 UTCEPSS rescoreEPSS 7.5% · 94th percentile
  24. 2026-10-25 14:18 UTCEG score recompute
  25. 2026-10-24 16:33 UTCEPSS rescoreEPSS 7.5% · 94th percentile
Show 75 more
  1. 2026-10-24 16:32 UTCEG score recompute
  2. 2026-10-24 16:32 UTCGHSA enrichmentGHSA-8rhx-2hcv-q49g · GitHub severity HIGH · GitHub CVSS 9.9
  3. 2026-10-23 16:32 UTCEPSS rescoreEPSS 7.5% · 94th percentile
  4. 2026-10-23 15:32 UTCEG score recompute
  5. 2026-10-23 15:32 UTCGHSA enrichmentGHSA-8rhx-2hcv-q49g · GitHub severity HIGH · GitHub CVSS 9.9
  6. 2026-10-22 16:34 UTCEPSS rescoreEPSS 7.5% · 94th percentile
  7. 2026-10-22 14:33 UTCEG score recompute
  8. 2026-10-22 14:32 UTCGHSA enrichmentGHSA-8rhx-2hcv-q49g · GitHub severity HIGH · GitHub CVSS 9.9
  9. 2026-10-21 16:33 UTCEPSS rescoreEPSS 7.5% · 94th percentile
  10. 2026-10-21 13:32 UTCEG score recompute
  11. 2026-10-21 13:32 UTCGHSA enrichmentGHSA-8rhx-2hcv-q49g · GitHub severity HIGH · GitHub CVSS 9.9
  12. 2026-10-20 16:33 UTCEPSS rescoreEPSS 7.5% · 94th percentile
  13. 2026-10-20 12:35 UTCEG score recompute
  14. 2026-10-20 12:35 UTCGHSA enrichmentGHSA-8rhx-2hcv-q49g · GitHub severity HIGH · GitHub CVSS 9.9
  15. 2026-10-19 16:32 UTCEPSS rescoreEPSS 7.5% · 94th percentile
  16. 2026-10-19 11:35 UTCEG score recompute
  17. 2026-10-19 11:34 UTCGHSA enrichmentGHSA-8rhx-2hcv-q49g · GitHub severity HIGH · GitHub CVSS 9.9
  18. 2026-10-18 16:32 UTCEPSS rescoreEPSS 7.5% · 94th percentile
  19. 2026-10-18 09:20 UTCGHSA enrichmentGHSA-8rhx-2hcv-q49g · GitHub severity HIGH · GitHub CVSS 9.9
  20. 2026-10-18 03:29 UTCEG score recompute
  21. 2026-10-17 16:34 UTCEPSS rescoreEPSS 7.5% · 94th percentile
  22. 2026-10-17 08:20 UTCEG score recompute
  23. 2026-10-17 08:20 UTCGHSA enrichmentGHSA-8rhx-2hcv-q49g · GitHub severity HIGH · GitHub CVSS 9.9
  24. 2026-10-16 16:42 UTCEPSS rescoreEPSS 7.5% · 94th percentile
  25. 2026-10-16 07:20 UTCEG score recompute
  26. 2026-10-16 07:20 UTCGHSA enrichmentGHSA-8rhx-2hcv-q49g · GitHub severity HIGH · GitHub CVSS 9.9
  27. 2026-10-15 16:32 UTCEPSS rescoreEPSS 7.5% · 94th percentile
  28. 2026-10-15 06:15 UTCEG score recompute
  29. 2026-10-15 06:15 UTCGHSA enrichmentGHSA-8rhx-2hcv-q49g · GitHub severity HIGH · GitHub CVSS 9.9
  30. 2026-10-14 16:33 UTCEPSS rescoreEPSS 7.5% · 94th percentile
  31. 2026-10-14 01:54 UTCEG score recompute
  32. 2026-10-14 01:54 UTCGHSA enrichmentGHSA-8rhx-2hcv-q49g · GitHub severity HIGH · GitHub CVSS 9.9
  33. 2026-10-13 16:34 UTCEPSS rescoreEPSS 7.5% · 94th percentile
  34. 2026-10-12 22:11 UTCEG score recompute
  35. 2026-10-12 22:10 UTCGHSA enrichmentGHSA-8rhx-2hcv-q49g · GitHub severity HIGH · GitHub CVSS 9.9
  36. 2026-10-12 16:34 UTCEPSS rescoreEPSS 7.5% · 94th percentile
  37. 2026-10-12 15:55 UTCEG score recompute
  38. 2026-10-12 06:49 UTCGHSA enrichmentGHSA-8rhx-2hcv-q49g · GitHub severity HIGH · GitHub CVSS 9.9
  39. 2026-10-11 19:38 UTCEG score recompute
  40. 2026-10-11 16:53 UTCEG score recompute
  41. 2026-10-11 14:16 UTCEG score recompute
  42. 2026-10-11 13:49 UTCEPSS rescoreEPSS 7.5% · 94th percentile
  43. 2026-10-10 20:00 UTCEPSS rescoreEPSS 7.5% · 94th percentile
  44. 2026-10-09 20:07 UTCEPSS rescoreEPSS 7.5% · 94th percentile
  45. 2026-10-08 17:13 UTCEPSS rescoreEPSS 7.5% · 94th percentile
  46. 2026-10-08 04:24 UTCOSV refresh
  47. 2026-10-07 23:48 UTCEPSS rescoreEPSS 7.5% · 94th percentile
  48. 2026-10-06 15:18 UTCEPSS rescoreEPSS 7.5% · 94th percentile
  49. 2026-10-05 17:43 UTCEPSS rescoreEPSS 7.5% · 94th percentile
  50. 2026-10-03 14:26 UTCEPSS rescoreEPSS 7.5% · 94th percentile
  51. 2026-10-02 17:56 UTCEPSS rescoreEPSS 7.5% · 94th percentile
  52. 2026-10-01 19:50 UTCEPSS rescoreEPSS 7.5% · 94th percentile
  53. 2026-09-30 15:03 UTCEPSS rescoreEPSS 7.5% · 94th percentile
  54. 2026-09-29 15:22 UTCEPSS rescoreEPSS 7.5% · 94th percentile
  55. 2026-09-28 13:51 UTCEPSS rescoreEPSS 7.5% · 94th percentile
  56. 2026-09-27 13:48 UTCEPSS rescoreEPSS 7.5% · 94th percentile
  57. 2026-09-26 15:59 UTCEPSS rescoreEPSS 7.5% · 94th percentile
  58. 2026-09-24 14:04 UTCEPSS rescoreEPSS 7.5% · 94th percentile
  59. 2026-09-23 17:54 UTCEPSS rescoreEPSS 7.5% · 94th percentile
  60. 2026-09-18 19:28 UTCEPSS rescoreEPSS 7.5% · 94th percentile
  61. 2026-09-18 10:29 UTCEG score recompute
  62. 2026-09-18 10:29 UTCGHSA enrichmentGHSA-8rhx-2hcv-q49g · GitHub severity HIGH · GitHub CVSS 9.9
  63. 2026-09-17 19:31 UTCEPSS rescoreEPSS 7.5% · 94th percentile
  64. 2026-09-16 14:08 UTCEPSS rescoreEPSS 7.5% · 94th percentile
  65. 2026-09-16 05:15 UTCEPSS rescoreEPSS 7.5% · 94th percentile
  66. 2026-09-15 03:11 UTCEPSS rescoreEPSS 7.5% · 94th percentile
  67. 2026-09-14 06:22 UTCGHSA enrichmentGHSA-8rhx-2hcv-q49g · GitHub severity HIGH · GitHub CVSS 9.9
  68. 2026-09-14 02:06 UTCGHSA enrichmentGHSA-8rhx-2hcv-q49g · GitHub severity HIGH · GitHub CVSS 9.9
  69. 2026-09-13 12:26 UTCEG score recompute
  70. 2026-09-13 12:26 UTCGHSA enrichmentGHSA-8rhx-2hcv-q49g · GitHub severity HIGH · GitHub CVSS 9.9
  71. 2026-09-11 14:53 UTCEPSS rescoreEPSS 7.5% · 94th percentile
  72. 2026-09-10 09:35 UTCEPSS rescoreEPSS 7.5% · 94th percentile
  73. 2026-09-08 22:01 UTCEPSS rescoreEPSS 7.5% · 94th percentile
  74. 2026-09-07 16:01 UTCEPSS rescoreEPSS 7.5% · 94th percentile
  75. 2026-09-06 13:47 UTCEPSS rescoreEPSS 7.5% · 94th percentile

Publicly available exploits

(1 reference)

Public exploit code is referenced for this CVE (1 Metasploit module). Defenders should treat patch urgency accordingly.

  • Metasploitexploit/multi/http/flowise_mcp_rce✓ verified
    Published Aug 20, 2026

    Flowise MCP Server Remote Code Execution

    Open source ↗

Frequently asked(5)

What is CVE-2026-56274?
CVE-2026-56274 is a critical-severity vulnerability; its CVE record was published on June 23, 2026. Flowise before 3.1.2 contains multiple OS command injection vulnerabilities in the Custom MCP Server feature due to incomplete command-flag validation and a regex bypass in local file access restrictions. An attacker with a Flowise account of any role, or API access with view/update permissions for…
When was CVE-2026-56274 made public?
CVE-2026-56274 was made public on May 14, 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 June 23, 2026. EchelonGraph's copy of the record carries a last-modified date of June 25, 2026; the record at its source may have been updated since.
Is CVE-2026-56274 actively exploited?
CVE-2026-56274 is not currently on CISA's Known Exploited Vulnerabilities catalog. EchelonGraph's EG-KEV model places it in Tier 2 (Weaponized), which is not evidence of exploitation: a Metasploit module exists for it. EchelonGraph does not test whether exploit code works. FIRST EPSS estimates a 7.5% probability of exploitation in the next 30 days (94th percentile of EPSS-scored CVEs).
What is the CVSS score of CVE-2026-56274?
CVE-2026-56274 has a CVSS base score of 9.9 (a secondary CVSS source that NVD displays; NVD's own analysis pending).
How do I remediate CVE-2026-56274?
A fix for CVE-2026-56274 is available: update to the fixed version the vendor names in its advisory. The vendor advisories EchelonGraph has for CVE-2026-56274 are linked in the Vendor Advisories panel on this page.

Dependency Blast Radius

See which npm, PyPI, Go, and Maven packages are affected by CVE-2026-56274

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