Security readout for executives and security teams
Plain-English summary
Flowise deployments can be exposed if they rely on built-in default JWT settings. In affected versions, missing environment variables cause publicly known secrets and issuer values to be used, which can let an attacker impersonate users, including administrators.
Executive priority
Treat as urgent for any internet-accessible or production Flowise deployment. The issue can undermine authentication completely when defaults are in use, so version and configuration validation should be prioritized immediately.
Technical view
Flowise before 3.1.0, including 3.0.13 and earlier, falls back to hardcoded JWT auth and refresh secrets plus default audience and issuer values in enterprise passport authentication middleware. If the related environment variables are unset, forged JWTs may be accepted, causing authentication bypass.
Likely exposure
Highest exposure is Flowise before 3.1.0 using enterprise passport authentication middleware without JWT_AUTH_TOKEN_SECRET, JWT_REFRESH_TOKEN_SECRET, JWT_AUDIENCE, or JWT_ISSUER explicitly configured.
Exploitation context
The bundle reports network-accessible, low-complexity, unauthenticated impact with full confidentiality, integrity, and availability consequences. KEV is false, and no cited source in the bundle confirms active exploitation.
Researcher notes
Evidence is specific to Flowise enterprise passport authentication middleware. Do not assume all configurations are exploitable; the described bypass depends on unset JWT-related environment variables causing fallback to known defaults.
Mitigation direction
- Upgrade Flowise to 3.1.0 or later where applicable.
- Set strong unique JWT_AUTH_TOKEN_SECRET and JWT_REFRESH_TOKEN_SECRET values.
- Set non-default JWT_AUDIENCE and JWT_ISSUER values.
- Rotate sessions or tokens after changing JWT secrets.
- Check Flowise vendor guidance for any additional remediation.
Validation and detection
- Inventory Flowise versions and identify deployments before 3.1.0.
- Confirm the four JWT environment variables are explicitly set.
- Verify values are not the documented defaults.
- Review authentication logs for unexpected administrator activity.
- Confirm upgraded systems still enforce intended authentication behavior.
Public sources used
Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.
Conservative CVE-to-ATT&CK context
These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.
ATT&CK lookup starting points
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CWE-321: Exact CWE lookup
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Open ATT&CK lookupCredential and access behavior lookup
The CVE wording references authentication or credential exposure, so valid-account and credential-access review may help. This is a Glexia inferred lookup path, not an official MITRE, ATT&CK, or CVE Program mapping.
Open ATT&CK lookupCVE-2026-56271 mapping review
Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.
Open ATT&CK lookup- Severity
- Critical
- CVSS
- 9.8 (3.1)
- Known Exploited
- No
- Published
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
CNA and ADP enrichment extracted from CVE v5
These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.
SSVC decision data
CVSS vector scores
2 official scoresWe collect every scored CVSS vector available in the official CNA and ADP containers. When more than one version is present, the table keeps the source vectors side by side instead of collapsing them into the highest score.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H3.95.9VulnCheckCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N——VulnCheckVulnerability scoring details
Base CVSS 4.0 score
9.3CriticalVector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
Base CVSS 3.1 score
9.8CriticalVector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Vulnerability timeline
Timeline events are normalized from CVE metadata, CNA source timelines, ADP timelines, and KEV metadata when present.
- CVE reservedCVE Program
The CVE ID was reserved by the assigning CNA.
- CVE publishedCVE Program
The CVE record was published.
- CVE updatedCVE Program
The CVE record metadata indicates this as the latest update time.
ADP provider summaries
Source materials
- CVE List V5 sourceCVE List V5
- GitHub Security Advisory (GHSA-cc4f-hjpj-g9p8)CVE reference, VulnCheck · vendor-advisory
- VulnCheck Advisory: Flowise - Weak Default JWT Secrets in Authentication MiddlewareCVE reference, VulnCheck · third-party-advisory
Products and packages named in the record
CWE details
CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.
Use of Hard-coded Cryptographic Key
Use of Hard-coded Cryptographic Key represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.