CVE-2026-19297 in Langflow OSS
Summary
by MITRE • 08/14/2026
IBM Langflow OSS 1.0.0 through 1.9.6 could allow a remote attacker to obtain unauthorized access to user accounts due to improper restriction of excessive authentication attempts.
Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.
Analysis
by VulDB Data Team • 08/14/2026
This vulnerability in IBM Langflow Open Source Software presents a significant authentication security flaw that could enable remote attackers to compromise user accounts through brute force or credential stuffing attacks. The issue stems from inadequate rate limiting and account lockout mechanisms that fail to properly restrict excessive authentication attempts, creating an opening for automated attack vectors. The vulnerability affects versions ranging from 1.0.0 through 1.9.6, indicating a prolonged period during which the software was susceptible to these types of unauthorized access attempts.
The technical nature of this flaw allows attackers to repeatedly attempt authentication with various credential combinations without sufficient system-enforced delays or account lockout procedures. This weakness directly violates security principles that mandate proper authentication controls and access management practices. The absence of effective rate limiting mechanisms means that attackers can systematically test multiple username and password combinations at high speeds, potentially exhausting legitimate user accounts through automated tools. This type of vulnerability is classified under CWE-307 - Improper Restriction of Excessive Authentication Attempts, which specifically addresses insufficient protection against brute force attacks.
The operational impact of this vulnerability extends beyond simple unauthorized access to encompass potential data breaches, privilege escalation, and system compromise. An attacker who successfully exploits this weakness could gain access to user accounts containing sensitive information, potentially leading to further lateral movement within the network or access to additional systems that rely on the compromised credentials. The remote nature of the attack means that threat actors do not require physical access to the system or network infrastructure, making this vulnerability particularly dangerous in cloud environments or distributed deployments where Langflow instances may be exposed to external traffic.
Organizations deploying IBM Langflow OSS versions within this affected range face substantial risk exposure given the accessibility of such authentication bypass vulnerabilities. The attack surface is amplified when considering that many automated systems and bots continuously scan for these types of weaknesses, making the window of opportunity for exploitation significant. Security teams must consider implementing immediate mitigations including network-level rate limiting, enhanced monitoring for suspicious authentication patterns, and potentially temporary account lockout procedures while more permanent solutions are implemented.
Recommended remediation strategies should include updating to a patched version of IBM Langflow OSS where proper authentication attempt restrictions have been implemented. Organizations should also consider implementing additional security controls such as multi-factor authentication, network segmentation, and comprehensive logging of authentication events for threat detection purposes. The vulnerability aligns with ATT&CK technique T1110 - Brute Force, specifically targeting credential access phases where adversaries attempt to gain access through repeated authentication attempts. This weakness represents a fundamental failure in access control implementation that directly undermines the security posture of any system relying on proper authentication mechanisms.