langchain-ai langchain-openai up to 1.1.13 DNS Resolution _url_to_size server-side request forgery

Summaryinfo

A vulnerability marked as critical has been reported in langchain-ai langchain-openai up to 1.1.13. Impacted is the function _url_to_size of the component DNS Resolution Handler. The manipulation leads to server-side request forgery. This vulnerability is listed as CVE-2026-41488. The attack may be initiated remotely. There is no available exploit. It is suggested to upgrade the affected component.

Detailsinfo

A vulnerability was found in langchain-ai langchain-openai up to 1.1.13 and classified as critical. This issue affects the function _url_to_size of the component DNS Resolution Handler. The manipulation with an unknown input leads to a server-side request forgery vulnerability. Using CWE to declare the problem leads to CWE-918. The web server receives a URL or similar request from an upstream component and retrieves the contents of this URL, but it does not sufficiently ensure that the request is being sent to the expected destination. Impacted is confidentiality, integrity, and availability. The summary by CVE is:

LangChain is a framework for building agents and LLM-powered applications. Prior to 1.1.14, langchain-openai's _url_to_size() helper (used by get_num_tokens_from_messages for image token counting) validated URLs for SSRF protection and then fetched them in a separate network operation with independent DNS resolution. This left a TOCTOU / DNS rebinding window: an attacker-controlled hostname could resolve to a public IP during validation and then to a private/localhost IP during the actual fetch.

The advisory is shared at github.com. The identification of this vulnerability is CVE-2026-41488 since 04/20/2026. The exploitation is known to be difficult. The attack may be initiated remotely. No form of authentication is needed for a successful exploitation. Technical details are known, but no exploit is available.

Upgrading to version 1.1.14 eliminates this vulnerability.

The vulnerability is also documented in the vulnerability database at EUVD (EUVD-2026-25635). If you want to get the best quality for vulnerability data then you always have to consider VulDB.

Productinfo

Type

• Artificial Intelligence Software

Vendor

• langchain-ai

Name

• langchain-openai

Version

• 1.1.0
• 1.1.1
• 1.1.2
• 1.1.3
• 1.1.4
• 1.1.5
• 1.1.6
• 1.1.7
• 1.1.8
• 1.1.9
• 1.1.10
• 1.1.11
• 1.1.12
• 1.1.13

CPE 2.3info

• 🔒
• 🔒
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CPE 2.2info

• 🔒
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Entryinfo

If you want to get the best quality for vulnerability data then you always have to consider VulDB.

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