CVE-2026-41481 LangChain: HTMLHeaderTextSplitter.split_text_from_url SSRF Redirect Bypass
Attackers can bypass SSRF protections in LangChain's HTMLHeaderTextSplitter to access internal endpoints via redirect bypass, potentially leaking sensitive data.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- A user has to click or open something
- Fix
- Available
What is CVE-2026-41481?
CVE-2026-41481 is a medium-severity server-side request forgery vulnerability in langchain-ai langchain-text-splitters, published on 24 Apr 2026. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.
Official description
LangChain is a framework for building agents and LLM-powered applications. Prior to langchain-text-splitters 1.1.2, HTMLHeaderTextSplitter.split_text_from_url() validated the initial URL using validate_safe_url() but then performed the fetch with requests.get() with redirects enabled (the default). Because redirect targets were not revalidated, a URL pointing to an attacker-controlled server could redirect to internal, localhost, or cloud metadata endpoints, bypassing SSRF protections. The response body is parsed and returned as Document objects to the calling application code. Whether this constitutes a data exfiltration path depends on the application: if it exposes Document contents (or derivatives) back to the requester who supplied the URL, sensitive data from internal endpoints could be leaked. Applications that store or process Documents internally without returning raw content to the requester are not directly exposed to data exfiltration through this issue. This vulnerability is fixed in 1.1.2.
Weakness: CWE-918
Which versions are affected by CVE-2026-41481?
3 open source packages ship an affected version, including langchain-text-splitters. It affects 1 product.
| Package | Affected | Fixed in |
|---|---|---|
langchain-text-splitters PyPI | All versions | 1.1.2 |
langchain-text-splitters PyPI | All versions | 1.1.2 |
langchain-text-splitters PyPI | All versions | 1.1.2 |
Products include Langchain Langchain-Text-Splitters.
How do I fix CVE-2026-41481?
Upgrade langchain-text-splitters to 1.1.2 or later.
Upgrade, and send outbound requests through an allow-list that blocks internal addresses. More about Server-side request forgery.
Is CVE-2026-41481 being exploited?
There is no known exploitation of CVE-2026-41481 in the wild and no public exploit code.
Sources
Also known as CLEANSTART-2026-VO66326, CLEANSTART-2026-VS88264, CLSA-2026-1779670108, ECHO-2692-dd04-73d6, GHSA-fv5p-p927-qmxr, PYSEC-2026-77 and 2 more.