Vulnerability · Published Aug 20, 2026 · Assigned by VulnCheck
CVE-2026-72848langchain-community SitemapLoader Does Not Apply restrict_to_same_domain to Nested Sitemap Index Entries, Allowing Server-Side Request Forgery
High 8.6
In plain English
A high-severity server-side request forgery in langchain-community from langchain-ai. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.6% (higher than 49% of all known vulnerabilities).
Official description
SitemapLoader.parse_sitemap in langchain_community/document_loaders/sitemap.py applies the documented restrict_to_same_domain control only to leaf url entries. The loop over url elements filters cross-domain locations, but the loop over nested sitemap elements passes the child loc straight to self.scrape_all([loc.text], "xml"), which reaches WebBaseLoader.scrape_all and an aiohttp GET, with no domain comparison and no check for private, loopback or link-local destinations. An attacker who controls or influences an ingested sitemap can therefore point a nested sitemap entry at an internal address and make the server fetch it even when the deploying application set restrict_to_same_domain to True specifically to confine outbound requests. The fetched content is parsed and surfaces in the returned Documents, so internal responses are disclosed to the caller rather than merely requested.
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| langchain-ai | langchain-community | 0 – through 0.4.2 |
Weakness: CWE-918 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:N/A:N
References
- GitHub Issue #38814 issue-tracking
- parse_sitemap leaf check and unguarded nested recursion technical-description
- https://github.com/langchain-ai/langchain-community product
- VulnCheck Advisory: langchain-community SitemapLoader Does Not Apply restrict_to_same_domain to Nested Sitemap Index Entries, Allowing Server-Side Request Forgery third-party-advisory