low3.1
CVE-2026-41488
langchain-openai: Image token counting SSRF protection can be bypassed via DNS rebinding
Impact
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 packages
| Ecosystem | Package | Affected | Fixed in |
|---|---|---|---|
| pip | langchain-openai | < 1.1.14 | 1.1.14 |
Affected products
| Vendor | Product | Affected versions |
|---|---|---|
| Langchain | Langchain-Openai | before 1.1.14 |
Weakness classification
References
- NVD record
- CVE.org record
- GitHub advisory
- https://github.com/advisories/GHSA-r7w7-9xr2-qq2r
- https://github.com/langchain-ai/langchain/security/advisories/GHSA-r7w7-9xr2-qq2r
- https://nvd.nist.gov/vuln/detail/CVE-2026-41488
- https://github.com/pypa/advisory-database/tree/main/vulns/langchain-openai/PYSEC-2026-76.yaml