CVE-2026-56278
CRITICALFlowise - Session Hijacking via Weak Default Express Session Secret
Title source: cnaDescription
Flowise before 3.1.0 (affected versions 3.0.13 and earlier) uses a weak hardcoded default secret ('flowise') for the express-session middleware when the EXPRESS_SESSION_SECRET environment variable is not set (packages/server/src/enterprise/middleware/passport/index.ts). Because this default secret is publicly visible in the source code, an attacker can forge valid signed session cookies to impersonate any user and bypass authentication.
References (2)
Core 2
Core References
Vendor Advisory vendor-advisory
GitHub Security Advisory (GHSA-2qqc-p94c-hxwh)
https://github.com/FlowiseAI/Flowise/security/advisories/GHSA-2qqc-p94c-hxwh
Third Party Advisory third-party-advisory
VulnCheck Advisory: Flowise - Session Hijacking via Weak Default Express Session Secret
https://www.vulncheck.com/advisories/flowise-session-hijacking-via-weak-default-express-session-secret
Scores
CVSS v3
9.1
EPSS
0.0037
EPSS Percentile
29.4%
Attack Vector
NETWORK
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
CISA SSVC
Vulnrichment
Exploitation
none
Automatable
yes
Technical Impact
total
Details
CWE
CWE-798
Status
published
Products (3)
Flowise/Flowise
< 3.1.0
Flowise/Flowise
3.1.0
flowiseai/flowise
< 3.1.0
Published
Jun 30, 2026
Tracked Since
Jul 01, 2026