CVE-2026-42048 | Langflow: Path Traversal in Langflow Knowledge Bases API

Exp

Langflow is a tool for building and deploying AI-powered agents and workflows. Prior to 1.9.0, Langflow is vulnerable to Path Traversal in the Knowledge Bases API (DELETE /api/v1/knowledge_bases). This occurs because user-supplied knowledge base names are concatenated directly into file paths without proper sanitization or boundary validation. An authenticated attacker can exploit this flaw to delete arbitrary directories anywhere on the server's filesystem, leading to data loss and potential service disruption. This vulnerability is fixed in 1.9.0.

Published: 2026-05-12 Last update: 2026-05-14 Assigner: [email protected] Source: [email protected]

Conclusion & alert: CVE-2026-42048 is rated Exploit Available (57.7/100): CVSS Critical severity, with low exploitation likelihood (EPSS 0.04%). Core evidence: 1 public exploit reference(s) are indexed (Exploit-DB). Mandatory action: Public exploits are available—assess exposure, apply mitigations, and prioritize patching.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Public exploit references (Exploit-DB) for CVE-2026-42048

EDB-ID Source Kind Published Link
nvd_ref exploit_tag Exploit-DB ↗

Exploit prediction scoring system (EPSS) score for CVE-2026-42048

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-05-13 0.04%

Full EPSS history (1 record total)

Common vulnerability scoring system (CVSS) metrics for CVE-2026-42048

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
9.6 3.1 CRITICAL
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:N/I:H/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:L)
A normal user session is enough; they don’t have to be admin.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:C)
Breaking this can reach past the original component and bite other resources—bigger blast radius.
Confidentiality (C:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
3.1 5.8 [email protected]

Weakness enumeration for CVE-2026-42048

GitHub Security Advisory for CVE-2026-42048

GHSA-9whx-c884-c68q · Severity: critical · Ecosystem: pip — Langflow Knowledge Bases API is Vulnerable to Path Traversal

Affected software / configurations for CVE-2026-42048

Vendor Product Version Raw CPE
langflow langflow < 1.9.0 cpe:2.3:a:langflow:langflow:*:*:*:*:*:*:*:*

References for CVE-2026-42048

cvelogic Threat Intelligence