Langflow Langflow: Langflow Origin Validation Error Vulnerability
› Langflow Langflow
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- started
- May 21, 2026
- closed
- May 21, 2026
- CVEs
- 1
- sources
- 3
## summary
Langflow contains an origin validation error vulnerability in which an overly permissive CORS configuration combined with a refresh token cookie configured as SameSite=None allows a malicious webpage to perform cross-origin requests that include credentials and successfully call the refresh endpoint. This could allow the attacker to execute arbitrary code and achieve full system compromise via obtained tokens that permit access to authenticated endpoints. Added to CISA KEV on 2026-05-21.
severity: Actively exploited (CISA KEV)
## cve ids[1]
## affected
- See vendor advisory / CISA notes (versions not always listed in KEV feed)
## fixed in
- See vendor advisory linked in sources
## timeline[1]
CISA added CVE-2025-34291 to the KEV catalog (due 2026-06-04).
## advisories[2]
## news & write-ups[1]
## notes & caveats
Derived from CISA KEV JSON feed catalogVersion 2026.10.21. Exact affected/fixed version strings are not always in the KEV record — verify against the vendor advisory URL. startedAt uses dateAdded (exploitation may have begun earlier).
