Answer in brief
CVE-2026-55255 records a Critical severity (CVSS 9.9) vulnerability in Langflow: IDOR Vulnerability in `/api/v1/responses` Endpoint Allows Authenticated Attackers to Access Another User's Flow. The current sources mark it as known exploited. The current feed maps langflow-ai/langflow (generic), langflow (pip). Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
CVSS is 9.9. Known-exploitation status makes exposure review time-sensitive. Treat this as a source-backed prioritization signal, not a statement about your environment.
Analysis status
Analysis pending evidence review
Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.
The current feed maps langflow-ai/langflow (generic), langflow (pip). Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| langflow-ai/langflowgeneric | < 1.9.1 | Not reported |
| langflowpip | <1.9.1 | 1.9.1 |
Published upstream
Jun 23, 2026
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Jul 10, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Jun 19, 2026
Added to CISA KEV
Jul 7, 2026
Evidence: source:kev:kev:kev:recordLangflow is a tool for building and deploying AI-powered agents and workflows. Prior to 1.9.1, an Insecure Direct Object Reference (IDOR) vulnerability in /api/v1/responses endpoint allows an authenticated attacker to execute any flow belonging to another user by specifying the victim's flow ID in the request. This vulnerability is fixed in 1.9.1.
Quoted source text, attributed separately from HOL analysis.