CVE-2026-41488 — angchain-openai: Image token counting SSRF protection can be bypassed via DNS rebinding

CVE-2026-41488

angchain-openai: Image token counting SSRF protection can be bypassed via DNS rebinding PUBLISHED

Description (CNA)

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.

Affected (CNA)

Vendor / product	Versions
langchain-ai / langchain-openai	affected < 1.1.14

CWE

CWE-918

References

https://github.com/langchain-ai/langchain/security/advisories/GHSA-r7w7-9xr2-qq2r

ADP enrichment

CISA-ADP

No English description supplied.

No references supplied.