CVEs / CVE-2025-34291
CVE-2025-34291: Langflow Origin Validation Error Vulnerability
- Known exploited in the CISA KEV catalog since 21 May 2026
- high 8.8 CVSS 3.1 (NVD)
- EPSS 92.8% chance of exploitation in the next 30 days, higher than 99% of CVEs (30 Oct 2026)
- Last changed at its sources
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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.
Description
Langflow versions up to and including 1.6.9 contain a chained vulnerability that enables account takeover and remote code execution. An overly permissive CORS configuration (allow_origins='*' with allow_credentials=True) 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. An attacker-controlled origin can therefore obtain fresh access_token / refresh_token pairs for a victim session. Obtained tokens permit access to authenticated endpoints — including built-in code-execution functionality — allowing the attacker to execute arbitrary code and achieve full system compromise.
Affected and fixed versions
| Product | Affected | Fixed in |
|---|---|---|
| Langflow Langflow | up to and including 1.6.9 | — |
| Product | Affected | Fixed in |
|---|---|---|
| langflow (PyPI) | before 1.7.0 | 1.7.0 |
Package versions from GHSA-577h-p2hh-v4mv.
Exploitation
| In CISA KEV since | 21 May 2026 |
|---|---|
| Due date for US federal agencies | 4 Jun 2026 |
| Used in ransomware campaigns | Unknown |
| Required action | Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable. |
Severity
| CVSS 3.1 | 8.8 highCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:HScored by NVD |
|---|---|
| Weakness | CWE-346 |
References
- CVE-2025-34291 on NVD
- CVE-2025-34291 in the CISA KEV catalog
- https://github.com/langflow-ai/langflow (cited by CISA)
- https://github.com/langflow-ai/langflow/releases/tag/v1.9.3 (cited by CISA)
- https://github.com/langflow-ai/langflow/issues/11465#event-25774545848 (cited by CISA)
- CVE-2025-34291 on OSV
- https://github.com/langflow-ai/langflow Product
- https://www.obsidiansecurity.com/blog/cve-2025-34291-critical-account-takeover-and-rce-vulnerability-in-the-langflow-ai-agent-workflow-platform Exploit, Mitigation, Third Party Advisory
- https://www.vulncheck.com/advisories/langflow-cors-misconfiguration-to-token-hijack-and-rce Third Party Advisory
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2025-34291 US Government Resource
- https://www.crowdsec.net/vulntracking-report/cve-2025-34291 Third Party Advisory
Sources
Exploitation status from the CISA Known Exploited Vulnerabilities catalog. EPSS scores from FIRST. Descriptions, severity and references from the National Vulnerability Database. Open-source package versions from OSV (CC-BY 4.0). Text is shown as each source states it; Stackurity does not edit it. Check the vendor's advisory before acting.
This product uses data from the NVD API but is not endorsed or certified by the NVD.