high Known exploitedREV. 01

CVE-2025-34291Langflow — permissive cross-origin policy to account takeover

Langflow up to 1.6.9 accepts credentialed requests from any origin (CORS) and ships its refresh cookie without a same-site restriction, so a page the victim visits can lift their session tokens and drive the built-in code execution.

YOUR NEXT MOVE

Upgrade Langflow past 1.6.9 now and narrow the allowed origins; invalidate every existing session and review run history for code executed with a stolen token.

Read the risk

THE VITAL STATS
CVSS score
8.8/ 10
CVSS v3.1
EPSS probability
84%
Likelihood of exploitation
Attack complexity
Low
Conditions needed to exploit
Known exploited
Yes — CISA KEV
CVE published
2025-12-05
Added to KEV
2026-05-21
Exploit published
Yes
Confidence
high
Kill chain
credential access
MITRE ATT&CK
—
Severity
high

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Attacker needsA signed-in Langflow user must visit an attacker-controlled page while their session is still live.

Behind the card

5 REFERENCES
Field-level provenanceTRACE THE SOURCES +

Which source supports each field, when it was retrieved, and who extracted it.

FieldsSourceRetrievedExtractorConfidence
cvss, exploitation.attack_complexity, exploitation.exploit_available, references, published_atnvd.nist.gov2026-09-24scrty-crds-pipeline/0.1high
exploitation.known_exploited, exploitation.kev_addedcisa.gov2026-09-24scrty-crds-pipeline/0.1high
epssapi.first.org2026-09-24scrty-crds-pipeline/0.1high
title, summary, severity, remediation, mitre_attack, kill_chain, recommended_action, confidence, tags, exploitation.prerequisitesnvd.nist.gov2026-09-24claude-codehigh

Printing history

THE RECORD
  1. r1Initial base card

First printing. This card has not been reprinted since publication.

crds:cve-2025-34291 · CRDS 0.1 · Issued 2026-09-24