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.

CVE-2026-72848 describes a Server-Side Request Forgery (SSRF) vulnerability in the LangChain Community library's SitemapLoader component. The restrict_to_same_domain parameter, intended to confine outbound HTTP requests to the original domain, is only enforced for leaf URL entries and not for nested sitemap index entries. An attacker who can influence or control an ingested sitemap can insert nested sitemap entries pointing to internal, loopback, or link-local addresses. These URLs are passed directly to WebBaseLoader.scrape_all via aiohttp GET requests without any domain or IP range validation. The fetched internal content is then parsed and returned as Documents to the caller, resulting in disclosure of internal service responses. This vulnerability affects applications using langchain-community's SitemapLoader with restrict_to_same_domain=True, providing a false sense of security. Remediation requires applying domain and private IP checks to nested sitemap element processing in sitemap.py.