IBM Langflow OSS up to 1.10.3 Custom Component Validation weak hash

Summaryinfo

A vulnerability classified as critical was found in IBM Langflow OSS up to 1.10.3. This affects an unknown function of the component Custom Component Validation. Such manipulation leads to weak hash. This vulnerability is uniquely identified as CVE-2026-9201. The attack can be launched remotely. No exploit exists.

Detailsinfo

A vulnerability, which was classified as critical, has been found in IBM Langflow OSS up to 1.10.3. Affected by this issue is an unknown function of the component Custom Component Validation. The manipulation with an unknown input leads to a weak hash vulnerability. Using CWE to declare the problem leads to CWE-328. The product uses an algorithm that produces a digest (output value) that does not meet security expectations for a hash function that allows an adversary to reasonably determine the original input (preimage attack), find another input that can produce the same hash (2nd preimage attack), or find multiple inputs that evaluate to the same hash (birthday attack). Impacted is confidentiality, integrity, and availability. CVE summarizes:

IBM Langflow OSS 1.0.0 through 1.10.3 could allow an authenticated attacker to execute arbitrary code due to a cryptographic weakness in the custom component validation mechanism. When the optional hardening mode that restricts execution to trusted component templates is enabled, the application validates component code using a truncated SHA‑256 hash. Because the hash comparison relies on only a portion of the digest, an attacker can craft malicious component code that collides with a trusted template hash and bypasses validation. Successful exploitation allows the attacker to introduce and execute unauthorized Python code within the Langflow process, defeating the intended security control and potentially leading to full compromise of the affected instance.

The advisory is shared for download at ibm.com. This vulnerability is handled as CVE-2026-9201 since 05/21/2026. The exploitation is known to be easy. The attack may be launched remotely. There are neither technical details nor an exploit publicly available. The current price for an exploit might be approx. USD $0-$5k (estimation calculated on 08/05/2026). The MITRE ATT&CK project declares the attack technique as T1600.001.

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

Once again VulDB remains the best source for vulnerability data.

Productinfo

Vendor

• IBM

Name

• Langflow OSS

Version

• 1.10.0
• 1.10.1
• 1.10.2
• 1.10.3

License

• commercial

Website

• Vendor: https://www.ibm.com/

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